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		<title>Tecnologia e non solo</title>
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		<item>
		<title>Deluge e debian sid.</title>
		<link>http://telperion.wordpress.com/2013/06/08/deluge-e-debian-sid/</link>
		<comments>http://telperion.wordpress.com/2013/06/08/deluge-e-debian-sid/#comments</comments>
		<pubDate>Sat, 08 Jun 2013 13:18:02 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Sid]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3237</guid>
		<description><![CDATA[Da qualche giorno Deluge crashava senza speranza rimuovendo un torrent. Trovato un ticket, applicata la patch, e ora rifunziona.<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3237&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>Da qualche giorno Deluge crashava senza speranza rimuovendo un torrent.<br />
Trovato un <a href="http://dev.deluge-torrent.org/ticket/2160" target="_blank">ticket</a>, applicata <a href="http://dev.deluge-torrent.org/attachment/ticket/2160/lt_gil_fix.patch" target="_blank">la patch</a>, e ora rifunziona. </p>
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		<title>FFmpeg static per Debian7/Ubuntu13.04 64bit</title>
		<link>http://telperion.wordpress.com/2013/05/30/ffmpeg-static-per-debian7ubuntu13-04-64bit/</link>
		<comments>http://telperion.wordpress.com/2013/05/30/ffmpeg-static-per-debian7ubuntu13-04-64bit/#comments</comments>
		<pubDate>Thu, 30 May 2013 16:49:02 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3219</guid>
		<description><![CDATA[ffmpeg (snapshoot vedi data deb) compilazione statica per Debian 7 Ubuntu 13.04 a 64bit, con supporto ai principali codec e alla libvidstab, libreria per stabilizzare i video in 2 passate. ffmpeg-static_20130614_amd64.deb Dipendenze: Depends: libc6 (&#62;= 2.15), zlib1g (&#62;= 1:1.2.0) quindi qualsiasi distribuzione debian derivata a 64bit che soddisfi quei due pacchetti, dovrebbe andare bene. Per [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3219&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>ffmpeg (snapshoot vedi data deb) <strong>compilazione statica</strong> per Debian 7 Ubuntu 13.04 a <strong>64bit</strong>,<br />
con supporto ai principali codec e <a href="http://telperion.wordpress.com/2013/04/25/ffmpeg-e-vid-stab-transcode-video-stabilization-plugin/" target="_blank">alla libvidstab</a>, libreria per stabilizzare i video in 2 passate.</p>
<p><strong><a href="https://dl.dropboxusercontent.com/u/77821647/ffmpeg-static_20130614_amd64.deb">ffmpeg-static_20130614_amd64.deb</a></strong></p>
<p>Dipendenze: Depends: libc6 (&gt;= 2.15), zlib1g (&gt;= 1:1.2.0)<br />
quindi qualsiasi distribuzione debian derivata a 64bit che soddisfi quei due pacchetti, dovrebbe andare bene. Per altre distribuzioni che non usano i deb, estraete dal pacchetto (con file-roller, ark) l&#8217;eseguibile e mettetelo dove più vi aggrada. </p>
<p><span id="more-3219"></span></p>
<p>L&#8217;eseguibile (in /usr/bin) si chiama<br />
<strong>ffmpeg-static</strong><br />
ed essendo statico comprende tutte le librerie, senza interferire con le lib di sistema.</p>
<p>Esempio di uso dei filtri di libvidstab</p>
<p><strong>prima passata col filtro vidstabdetect:</strong></p>
<p><code>ffmpeg-static -y -i test.mkv -vf vidstabdetect -an -f rawvideo /dev/null</code><br />
che produrra solo il file transforms.trf, necessario al filtro vidstabtransform</p>
<p><strong>seconda passata col filtro vidstabtransform</strong></p>
<p><code>ffmpeg-static -i test.mkv -vf vidstabtransform  -c:v libx264 -preset faster -tune film -b:v 850k -c:a libfdk_aac -b:a 112k -f matroska stabilizzato.mkv<br />
</code></p>
<p><strong><a href="http://www.ffmpeg.org/ffmpeg-filters.html#vidstabdetect" target="_blank">Maggiori info sull&#8217;uso di libvidstab qua</a></strong>.</p>
<p><strong><a href="http://www.ffmpeg.org/ffmpeg-filters.html" target="_blank">Lista dei filtri di ffmpeg qua.</a></strong></p>
<p>Per la lista dei codecs supportati<br />
<code>ffmpeg-static -codecs</code></p>
<p>help per encoder (esempio libx264)<br />
<code>ffmpeg-static -h encoder=libx264</code></p>
<p>Per la lista dei filtri supportati<br />
<code>ffmpeg-static -filters</code></p>
<p>help per filtro (esempio crop)<br />
<code>ffmpeg-static -h filter=crop</code></p>
<p><strong><a href="http://www.ffmpeg.org/documentation.html" target="_blank">Help completo online qui.</a></strong></p>
<p>Qui invece trovate ffmpeg10-static</p>
<p><strong><a href="https://dl.dropboxusercontent.com/u/77821647/ffmpeg10-static_20130614_amd64.deb">ffmpeg10-static_20130614_amd64.deb</a></strong></p>
<p>che è la stessa versione ma compilata con <strong>libx264 con bit-depth=10</strong>,<br />
se comprimete con codec libx264, otterrete dei file profile High 10, 10-bit.<br />
Per usarlo lanciate:</p>
<p><strong>ffmpeg10-static</strong></p>
<p>Entrambe le versioni possono essere installate contemporaneamente,<br />
e coesistere senza problemi con ffmpeg e avconv di sistema</p>
<p><strong>ATTENZIONE:<br />
Usate il software solo per uso personale, a vostro completo rischio e pericolo. </strong></p>
<br />  <a rel="nofollow" href="http://feeds.wordpress.com/1.0/gocomments/telperion.wordpress.com/3219/"><img alt="" border="0" src="http://feeds.wordpress.com/1.0/comments/telperion.wordpress.com/3219/" /></a> <img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3219&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></content:encoded>
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		<item>
		<title>x264 OpenCL lookahead, test 2</title>
		<link>http://telperion.wordpress.com/2013/05/21/x264-opencl-lookahead-test-2/</link>
		<comments>http://telperion.wordpress.com/2013/05/21/x264-opencl-lookahead-test-2/#comments</comments>
		<pubDate>Tue, 21 May 2013 11:53:21 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3198</guid>
		<description><![CDATA[Un nuovo commit per x264 (versione 133), vediamo se migliora le performance di OpenCL che come visto nel test precedente non erano stati particolarmente brillanti. Solita piattaforma, debian sid 64, Intel Q8300, NVIDIA GeForce GT 440. Ora non è più necessario modificare il configure, in presenza delle librerie OpenCL, il supporto viene attivato automaticamente. e [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3198&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>Un nuovo <strong><a href="http://git.videolan.org/?p=x264.git;a=commitdiff;h=a3ac64b8b467eea1264c0053022893bc84b2e9a2" target="_blank">commit</a></strong> per x264 (versione 133), vediamo se migliora le performance di OpenCL che come visto nel <a href="http://telperion.wordpress.com/2013/05/09/x264-opencl-lookahead-test/" target="_blank">test precedente</a> non erano stati particolarmente brillanti.</p>
<p><span id="more-3198"></span></p>
<p>Solita piattaforma, debian sid 64, Intel Q8300, NVIDIA GeForce GT 440.</p>
<p>Ora non è più necessario modificare il configure, in presenza delle librerie OpenCL, il supporto viene attivato automaticamente. e si compila anche la libreria condivisa.<br />
Anche via ffmpeg si può attivare OpenCL con<br />
<code>-x264opts opencl</code>.</p>
<p><strong>Senza OpenCL</strong><br />
<code>$ time ./x264 --threads 0 --sar 4:3  \<br />
--bitrate 1800 --preset fast --tune film \<br />
-o video.mkv /media/scambio/Amazing_Caves_1080.wmv </p>
<p>lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: profile High, level 4.0</p>
<p>encoded 2037 frames, 24.58 fps, 1640.35 kb/s</p>
<p>real    1m22.962s</code><br />
1 minuto e 23 secondi.</p>
<p><strong>Con OpenCl</strong><br />
<code>$ time ./x264 --threads 0 --opencl --sar 4:3 \<br />
 --bitrate 1800 --preset fast --tune film \<br />
-o video.mkv /media/scambio/Amazing_Caves_1080.wmv </p>
<p>lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: OpenCL acceleration enabled with NVIDIA Corporation GeForce GT 440<br />
x264 [info]: profile High, level 4.0</p>
<p>encoded 2037 frames, 25.72 fps, 1637.46 kb/s</p>
<p>real    1m19.390s</code><br />
1 minuto e 19 secondi circa.</p>
<p><strong>Con il preset slow (rc-lookahead 50 contro rc-lookahead 20 di faster).</strong></p>
<p><strong>Senza OpenCL</strong><br />
<code>$ time ./x264 --threads 0 --sar 4:3 \<br />
--bitrate 1800 --preset slow --pass 1 --tune film \<br />
-o /dev/null  /media/scambio/Amazing_Caves_1080.wmv </p>
<p>lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: profile Main, level 4.0</p>
<p>encoded 2037 frames, 34.57 fps, 1637.09 kb/s</p>
<p>real    0m59.130s</code><br />
poco più di 59 secondi.</p>
<p><strong>Con OpenCL</strong><br />
<code>$ time ./x264 --threads 0 --sar 4:3 \<br />
--bitrate 1800 --preset slow --opencl --pass 1 --tune film \<br />
-o /dev/null  /media/scambio/Amazing_Caves_1080.wmv </p>
<p>lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: OpenCL acceleration enabled with NVIDIA Corporation GeForce GT 440<br />
x264 [info]: profile Main, level 4.0</p>
<p>encoded 2037 frames, 30.93 fps, 1643.33 kb/s</p>
<p>real    1m6.115s</code><br />
1 minuto e 6 secondi.</p>
<p><strong>Stessi risultati usando ffmpeg.</strong></p>
<p><strong>Senza OpenCL</strong><br />
<code>$ time ffmpeg2 -y -i /media/scambio/Amazing_Caves_1080.wmv  \<br />
-threads 0 \<br />
-c:v libx264 -preset slow -tune film \<br />
-b:v 1800k -x264opts sar=4/3 \<br />
-pass 1 -fastfirstpass 1 -an \<br />
-f matroska /dev/null</p>
<p>ffmpeg version N-53323-gb8a9876 Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 21 2013 18:41:38 with gcc 4.7 (Debian 4.7.3-4)</p>
<p>  Duration: 00:01:25.50, start: 0.000000, bitrate: 8295 kb/s<br />
    Stream #0:0(eng): Audio: wmapro (b[1][0][0] / 0x0162), 48000 Hz, 5.1, fltp, 384 kb/s<br />
    Stream #0:1(eng): Video: wmv3 (Main) (WMV3 / 0x33564D57), yuv420p, 1440x1080, 8000 kb/s, SAR 4:3 DAR 16:9, 23.98 tbr, 1k tbn, 1k tbc<br />
[libx264 @ 0x194d720] using SAR=4/3<br />
[libx264 @ 0x194d720] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x194d720] profile Main, level 4.0<br />
[libx264 @ 0x194d720] 264 - core 133 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 \<br />
Output #0, matroska, to '/dev/null':</p>
<p>Stream mapping:<br />
  Stream #0:1 -&gt; #0:0 (wmv3 -&gt; libx264)<br />
Press [q] to stop, [?] for help<br />
frame= 2037 fps= 34 q=-1.0 Lsize=   16987kB time=00:01:24.87 bitrate=1639.5kbits/s<br />
video:16971kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.093150%</p>
<p>real    0m59.253s</code></p>
<p><strong>Con OpenCL</strong><br />
<code>$ time ffmpeg2 -y -i /media/scambio/Amazing_Caves_1080.wmv \<br />
 -threads 0 \<br />
-c:v libx264 -preset slow -tune film \<br />
-b:v 1800k -x264opts opencl:sar=4/3 \<br />
-pass 1 -fastfirstpass 1 -an \<br />
-f matroska /dev/null</p>
<p>ffmpeg version N-53323-gb8a9876 Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 21 2013 18:41:38 with gcc 4.7 (Debian 4.7.3-4)</p>
<p>  Duration: 00:01:25.50, start: 0.000000, bitrate: 8295 kb/s<br />
    Stream #0:0(eng): Audio: wmapro (b[1][0][0] / 0x0162), 48000 Hz, 5.1, fltp, 384 kb/s<br />
    Stream #0:1(eng): Video: wmv3 (Main) (WMV3 / 0x33564D57), yuv420p, 1440x1080, 8000 kb/s, SAR 4:3 DAR 16:9, 23.98 tbr, 1k tbn, 1k tbc<br />
[libx264 @ 0x3044720] using SAR=4/3<br />
[libx264 @ 0x3044720] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x3044720] OpenCL acceleration enabled with NVIDIA Corporation GeForce GT 440<br />
[libx264 @ 0x3044720] profile Main, level 4.0<br />
[libx264 @ 0x3044720] 264 - core 133 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013<br />
Output #0, matroska, to '/dev/null':</p>
<p>Stream mapping:<br />
  Stream #0:1 -&gt; #0:0 (wmv3 -&gt; libx264)<br />
Press [q] to stop, [?] for help<br />
frame= 2037 fps= 31 q=-1.0 Lsize=   17051kB time=00:01:24.87 bitrate=1645.7kbits/s<br />
video:17035kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.092664%</p>
<p>real    1m6.720s</code></p>
<p>Questi i carichi d lavoro della CPU nei 2 casi:<br />
<a target='_blank' title='ImageShack - Image And Video Hosting' href='http://imageshack.us/photo/my-images/600/x264oclcpu.png/'><img src='http://img600.imageshack.us/img600/36/x264oclcpu.png' border='0' /></a><br />Uploaded with <a target='_blank' href='http://imageshack.us'>ImageShack.us</a></p>
<p>OpenCL più lenta della Cpu,<br />
niente &#8220;miracoli velocistici&#8221; purtroppo.</p>
<p><a href="http://git.videolan.org/?p=x264.git&amp;a=search&amp;h=a3ac64b8b467eea1264c0053022893bc84b2e9a2&amp;st=commit&amp;s=opencl" target="_blank">Commit Opencl</a><br />
<em><a href="http://pastebin.com/raw.php?i=2aCak4v0" target="_blank">Altri test.</a></em></p>
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			<media:title type="html">telperion</media:title>
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		<title>Gimp 2.9.1 qualche novità.</title>
		<link>http://telperion.wordpress.com/2013/05/18/gimp-2-9-1-qualche-novita/</link>
		<comments>http://telperion.wordpress.com/2013/05/18/gimp-2-9-1-qualche-novita/#comments</comments>
		<pubDate>Sat, 18 May 2013 13:43:56 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[image-processing]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3193</guid>
		<description><![CDATA[Uploaded with ImageShack.us Aggiunta la canvas rotation, che funziona bene, ed il seamless clone, che invece imballa Gimp per tempi lunghissimi anche con selezioni piccole, per poi offrire risultati che non si riescono a trascinare nella posizione voluta ed a stampare sull&#8217;immagine base, insomma c&#8217;è molto da lavorarci su. Permane la lentezza della versione 2.9.1 [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3193&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p><a target='_blank' title='ImageShack - Image And Video Hosting' href='http://imageshack.us/photo/my-images/6/gimp291canvrot2.jpg/'><img src='http://img6.imageshack.us/img6/498/gimp291canvrot2.jpg' border='0' /></a><br />Uploaded with <a target='_blank' href='http://imageshack.us'>ImageShack.us</a></p>
<p>Aggiunta la <strong><a href="https://plus.google.com/+gimp/posts/4jH8KPuACwh" target="_blank">canvas rotation</a></strong>, che funziona bene, ed il <strong><a href="http://www.youtube.com/watch?v=pqVMt-ReaDc" target="_blank">seamless clone</a></strong>, che invece imballa <a href="https://plus.google.com/+gimp/posts/APripWXninz" target="_blank">Gimp per tempi lunghissimi</a> anche con selezioni piccole, per poi offrire risultati che non si riescono a trascinare nella posizione voluta ed a stampare sull&#8217;immagine base, insomma c&#8217;è molto da lavorarci su. </p>
<p>Permane la lentezza della versione 2.9.1 rispetto alla 2.8.4, tale da sconsigliarne ancora l&#8217;uso.</p>
<p><em>Immagine del test dalla rete</em></p>
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		<title>x264: comprimere a 10 bit con ffmpeg</title>
		<link>http://telperion.wordpress.com/2013/05/14/x264-comprimere-a-10-bit-con-ffmpeg/</link>
		<comments>http://telperion.wordpress.com/2013/05/14/x264-comprimere-a-10-bit-con-ffmpeg/#comments</comments>
		<pubDate>Tue, 14 May 2013 18:21:09 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3182</guid>
		<description><![CDATA[Ultimamente va di moda comprimere con x264 a 10 bit e profilo high 10. Vediamo come fare Con ffmpeg di sistema (che deve avere --enable-libx264 nella configurazione), esempio con debian-multimedia: ffmpeg version 1.0.7 Copyright (c) 2000-2013 the FFmpeg developers built on May 14 2013 06:27:36 with gcc 4.7 (Debian 4.7.3-4) o con una versione compilata [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3182&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>Ultimamente va di moda comprimere con x264 a 10 bit e profilo high 10.</p>
<p>Vediamo come fare</p>
<p><span id="more-3182"></span><br />
Con <strong>ffmpeg</strong> di sistema (<strong>che deve avere</strong> <code>--enable-libx264</code> <strong>nella configurazione</strong>),<br />
esempio con debian-multimedia:</p>
<p><code>ffmpeg version 1.0.7 Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 14 2013 06:27:36 with gcc 4.7 (Debian 4.7.3-4)</code></p>
<p>o con una versione compilata da voi, ad esempio:</p>
<p><code>ffmpeg version N-53043-g6b13f54 Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 14 2013 15:34:04 with gcc 4.7 (Debian 4.7.3-4)<br />
</code></p>
<p>cioè un 1.2+git-g6b13f54,<br />
viene usata la libx264 di sistema, che è compilata a 8 bit.</p>
<p>Per comprimere a 10 bit è necessario ricompilare x264 con il supporto ai 10 bit.<br />
Se avete come nel mio caso la libx264-132, potete scaricarvi uno <a href="http://git.videolan.org/?p=x264.git;a=snapshot;h=76a5c3a19f97cd34b65aeff050de4042b054bc65;sf=tgz">snapshot</a>, scompattarlo e compilarlo con:</p>
<p><code>./configure \<br />
--prefix=/opt/x264-10 \<br />
--extra-cflags='-g -O3 -fstack-protector \<br />
--param=ssp-buffer-size=4 -Wformat -Werror=format-security ' \<br />
--extra-ldflags='-Wl,-z,relro' \<br />
--enable-static \<br />
--enable-pic \<br />
--bit-depth=10 \<br />
--enable-visualize \<br />
--disable-lavf \<br />
--enable-shared</code></p>
<p>poi i soliti<br />
<code>make</code><br />
<code>sudo make install</code></p>
<p>installeranno la nuova lib in /opt/x264-10, senza disturbare il sistema.</p>
<p>Ora per far usare a ffmpeg la libreria, basta creare un wrapper:</p>
<p><code>#-------------------------------------<br />
#!/bin/sh</p>
<p>LD_LIBRARY_PATH=/opt/x264-10/lib<br />
export LD_LIBRARY_PATH</p>
<p>ffmpeg "$@"<br />
#-------------------------------------</code></p>
<p>salvatelo come</p>
<p><strong>ffmpeg-x10bit</strong></p>
<p>rendetelo eseguibile, e spostatelo in<br />
<code>/usr/local/bin/ffmpeg-x10bit</code></p>
<p>Ora se volete usare il normale 8bit lanciate ffmpeg,<br />
se volete usare il 10bit lanciate ffmpeg-x10bit.</p>
<p>Qualche test.</p>
<p><strong>10 bit</strong></p>
<p><code>ffmpeg-x10bit -y -i /home/mc/test.mkv -t 00:03:00 -c:v libx264 -profile high10 -preset faster -tune film -b:v 730k -an -f matroska out2.mkv<br />
ffmpeg version N-53043-g6b13f54 Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 14 2013 15:34:04 with gcc 4.7 (Debian 4.7.3-4)<br />
Input #0, matroska,webm, from '/home/mc/test.mkv':</p>
<p>  Duration: 00:42:56.21, start: 0.000000, bitrate: 845 kb/s<br />
    Stream #0:0(und): Video: h264 (High), yuv420p, 720x406, SAR 1:1 DAR 360:203</p>
<p>[libx264 @ 0x349f240] using SAR=1/1<br />
[libx264 @ 0x349f240] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x349f240] profile High 10, level 3.0, 4:2:0 10-bit<br />
[libx264 @ 0x349f240] 264 - core 132 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013</p>
<p>Output #0, matroska, to 'out2.mkv':<br />
frame= 4313 fps= 82 q=-1.0 Lsize=   16420kB time=00:02:59.93 bitrate= 747.6kbits/s<br />
video:16387kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.195247%</p>
<p>real    0m52.385s</code></p>
<p>52 secondi per un video 720&#215;406 di 3 minuti.</p>
<p><strong>8 bit:</strong></p>
<p><code>ffmpeg -y -i /home/mc/test.mkv -t 00:03:00 -c:v libx264 -profile high10 -preset faster -tune film -b:v 730k -an -f matroska out1.mkv<br />
ffmpeg version N-53043-g6b13f54 Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 14 2013 15:34:04 with gcc 4.7 (Debian 4.7.3-4)<br />
Input #0, matroska,webm, from '/home/mc/test.mkv':</p>
<p>  Duration: 00:42:56.21, start: 0.000000, bitrate: 845 kb/s<br />
    Stream #0:0(und): Video: h264 (High), yuv420p, 720x406, SAR 1:1 DAR 360:203</p>
<p>[libx264 @ 0x21fe240] using SAR=1/1<br />
[libx264 @ 0x21fe240] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x21fe240] profile High, level 3.0<br />
[libx264 @ 0x21fe240] 264 - core 132 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013</p>
<p>Output #0, matroska, to 'out1.mkv':<br />
frame= 4313 fps=124 q=-1.0 Lsize=   16436kB time=00:02:59.93 bitrate= 748.3kbits/s<br />
video:16404kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.195050%</p>
<p>real    0m34.758s</code></p>
<p>Solo 35 secondi per lo stesso video.</p>
<p>Se sia il caso di aumentare il tempo di compressione per avere i 10 bit, onestamente non saprei dirvi, non noto particolari differenze ad occhio.</p>
<p>Tenete poi presente che x264 a 10bit non viene accelerato da VDPAU durante la visione, e quindi va tutto a carico della cpu.</p>
<p>Il gioco vale la candela?<br />
Per me no, poi va a gusti.</p>
<p><strong>PS.</strong></p>
<p>Lo stesso giochetto, funziona anche con <strong>avconv</strong></p>
<p><code>mc@debian64:~/develop-deb/libav/0.8.7$ time ./avconv-x10bit -y -i /home/test.mkv -t 00:03:00 -c:v libx264 -profile high10 -preset faster -tune film -b:v 730k -an -f matroska out1.mkv<br />
avconv version 0.8.7, Copyright (c) 2000-2013 the Libav developers<br />
  built on May 14 2013 22:53:32 with gcc 4.7.3<br />
[matroska,webm @ 0x2801000] Estimating duration from bitrate, this may be inaccurate<br />
Input #0, matroska,webm, from '/home/test.mkv':</p>
<p>  Duration: 00:42:56.21, start: 0.000000, bitrate: N/A<br />
    Stream #0.0(und): Video: h264 (High), yuv420p, 720x406, PAR 1:1 DAR 360:203, 23.98 fps</p>
<p>Incompatible pixel format 'yuv420p' for codec 'libx264', auto-selecting format 'yuv420p10le'<br />
[buffer @ 0x287bea0] w:720 h:406 pixfmt:yuv420p<br />
[avsink @ 0x2877640] auto-inserting filter 'auto-inserted scaler 0' between the filter 'src' and the filter 'out'<br />
[scale @ 0x28785a0] w:720 h:406 fmt:yuv420p -&gt; w:720 h:406 fmt:yuv420p10le flags:0x4<br />
[libx264 @ 0x2832800] using SAR=1/1<br />
[libx264 @ 0x2832800] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x2832800] profile High 10, level 3.0, 4:2:0 10-bit<br />
[libx264 @ 0x2832800] 264 - core 132 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 </p>
<p>Output #0, matroska, to 'out1.mkv':<br />
  Metadata:<br />
    Stream #0.0(und): Video: libx264, yuv420p10le, 720x406 [PAR 1:1 DAR 360:203], q=-1--1, 730 kb/s, 1k tbn, 23.98 tbc (default)</p>
<p>Stream mapping:<br />
  Stream #0:0 -&gt; #0:0 (h264 -&gt; libx264)</p>
<p>frame= 4313 fps= 90 q=-1.0 Lsize=   16396kB time=179.97 bitrate= 746.3kbits/s<br />
video:16363kB audio:0kB global headers:0kB muxing overhead 0.195856%</p>
<p>real    0m48.258s<br />
</code></p>
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		<title>VP9 è &#8220;quasi&#8221; pronto?</title>
		<link>http://telperion.wordpress.com/2013/05/12/vp9-e-quasi-pronto/</link>
		<comments>http://telperion.wordpress.com/2013/05/12/vp9-e-quasi-pronto/#comments</comments>
		<pubDate>Sun, 12 May 2013 14:53:54 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3165</guid>
		<description><![CDATA[VP9 Codec Nears Completion VP9 è il successore di VP8, ed è (dovrebbe) un codec video HEVC Bene facciamo qualche test. Solita piattaforma, debian sid 64, cpu Intel Q8300. Compilati libvpx (sia il ramo master che l&#8217;experimental, stessi risultati) e ffmpeg da git per avere il supporto a VP9: ./ffmpeg-vp9 -codecs &#124; grep vp ffmpeg [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3165&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p><a href="http://blog.webmproject.org/2013/05/vp9-codec-nears-completion.html" target="_blank">VP9 Codec Nears Completion</a></p>
<p><a href="http://en.wikipedia.org/wiki/VP9" target="_blank">VP9</a> è il successore di VP8, ed è (<a href="http://en.wikipedia.org/wiki/High_Efficiency_Video_Coding" target="_blank">dovrebbe</a>) un codec video <strong><a href="http://it.wikipedia.org/wiki/High_Efficiency_Video_Coding" target="_blank">HEVC</a></strong></p>
<p>Bene facciamo qualche test.<br />
Solita piattaforma, debian sid 64, cpu Intel Q8300. </p>
<p><span id="more-3165"></span></p>
<p>Compilati <a href="http://git.chromium.org/gitweb/?p=webm/libvpx.git;a=summary" target="_blank">libvpx</a> (sia il ramo master che l&#8217;experimental, stessi risultati) e ffmpeg da git per avere il supporto a VP9:</p>
<p><code><br />
./ffmpeg-vp9 -codecs | grep vp<br />
ffmpeg version 1.1.git-90d35e5 Copyright (c) 2000-2013 the FFmpeg developers</p>
<p> D.V.L. vp3                  On2 VP3<br />
 D.V.L. vp5                  On2 VP5<br />
 D.V.L. vp6                  On2 VP6<br />
 D.V.L. vp6a                 On2 VP6 (Flash version, with alpha channel)<br />
 D.V.L. vp6f                 On2 VP6 (Flash version)<br />
 DEV.L. vp8                  On2 VP8 (decoders: vp8 libvpx ) (encoders: libvpx )<br />
 DEV.L. vp9                  Google VP9 (decoders: libvpx-vp9 ) (encoders: libvpx-vp9 )<br />
 D.A.LS wavpack              WavPack<br />
 D.S... vplayer              VPlayer subtitle<br />
</code></p>
<p>Vediamo i parametri:</p>
<p><code><br />
./ffmpeg-vp9 -h encoder=libvpx-vp9</p>
<p>Encoder libvpx-vp9 [libvpx VP9]:<br />
    Threading capabilities: no<br />
    Supported pixel formats: yuv420p<br />
libvpx encoder AVOptions:<br />
  -cpu-used                  E..V.. Quality/Speed ratio modifier (from INT_MIN to INT_MAX)<br />
  -auto-alt-ref              E..V.. Enable use of alternate reference frames (2-pass only) (from -1 to 1)<br />
  -lag-in-frames             E..V.. Number of frames to look ahead for alternate reference frame selection (from -1 to INT_MAX)<br />
  -arnr-maxframes            E..V.. altref noise reduction max frame count (from -1 to INT_MAX)<br />
  -arnr-strength             E..V.. altref noise reduction filter strength (from -1 to INT_MAX)<br />
  -arnr-type                 E..V.. altref noise reduction filter type (from -1 to INT_MAX)<br />
     backward                     E..V..<br />
     forward                      E..V..<br />
     centered                     E..V..<br />
  -deadline                  E..V.. Time to spend encoding, in microseconds. (from INT_MIN to INT_MAX)<br />
     best                         E..V..<br />
     good                         E..V..<br />
     realtime                     E..V..<br />
  -error-resilient         E..V.. Error resilience configuration<br />
     default                      E..V.. Improve resiliency against losses of whole frames<br />
     partitions                   E..V.. The frame partitions are independently decodable by the bool decoder, meaning that partitions can be decoded even though earlier partitions have been lost. Note that intra predicition is still done over the partition boundary.<br />
  -max-intra-rate            E..V.. Maximum I-frame bitrate (pct) 0=unlimited (from -1 to INT_MAX)<br />
  -speed                     E..V..  (from -16 to 16)<br />
  -quality                   E..V..  (from INT_MIN to INT_MAX)<br />
     best                         E..V..<br />
     good                         E..V..<br />
     realtime                     E..V..<br />
  -vp8flags                E..V..<br />
     error_resilient              E..V.. enable error resilience<br />
     altref                       E..V.. enable use of alternate reference frames (VP8/2-pass only)<br />
  -arnr_max_frames           E..V.. altref noise reduction max frame count (from 0 to 15)<br />
  -arnr_strength             E..V.. altref noise reduction filter strength (from 0 to 6)<br />
  -arnr_type                 E..V.. altref noise reduction filter type (from 1 to 3)<br />
  -rc_lookahead              E..V.. Number of frames to look ahead for alternate reference frame selection (from 0 to 25)<br />
  -crf                       E..V.. Select the quality for constant quality mode (from 0 to 63)<br />
</code></p>
<p>Via ai test, <strong>usate solo le 2 passate</strong>,<br />
perchè a singola passata con VP9 non c&#8217;è alcun controllo del bitrate,<br />
ed il risultato è *schifoso*.</p>
<p><strong>VP9 pass1 </strong><br />
<code><br />
time ./ffmpeg-vp9 -y -i /home/mc/test.mkv -t 00:00:30  -c:v libvpx-vp9 -strict -2 -quality good -b:v 600k -speed 16 -rc_lookahead 25 -pass 1 -an -f matroska  /dev/null</p>
<p>ffmpeg version 1.1.git-cd43a7e Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 12 2013 13:44:36 with gcc 4.7 (Debian 4.7.3-3)</p>
<p>Input #0, matroska,webm<br />
  Duration: 00:44:05.50, start: 0.000000, bitrate: 846 kb/s<br />
    Stream #0:0(eng): Video: h264 (High), yuv420p, 720x404, SAR 1:1 DAR 180:101, 25 fps<br />
[libvpx-vp9 @ 0x20da340] v1.2.0-2099-gb4e3909<br />
Output #0, matroska, to '/dev/null':<br />
    Stream #0:0(eng): Video: vp9 (libvpx-vp9) ([255][255][255][255] / 0xFFFFFFFF), yuv420p, 720x404 [SAR 1:1 DAR 180:101], q=-1--1, pass 1, 600 kb/s, 1k tbn, 25 tbc (default)</p>
<p>frame=  748 fps= 49 q=0.0 Lsize=       1kB time=00:00:00.00 bitrate=N/A<br />
video:0kB audio:0kB subtitle:0 global headers:0kB muxing overhead inf%</p>
<p>real    0m15.460s<br />
</code></p>
<p><strong>VP9 pass2</strong><br />
<code><br />
time ./ffmpeg-vp9 -y -i /home/mc/test.mkv -t 00:00:30  -c:v libvpx-vp9 -strict -2 -quality good -b:v 600k -speed 16 -rc_lookahead 25 -pass 2 -an -f matroska  out2.mkv </p>
<p>ffmpeg version 1.1.git-cd43a7e Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May 12 2013 13:44:36 with gcc 4.7 (Debian 4.7.3-3)</p>
<p>Input #0, matroska,webm<br />
  Duration: 00:44:05.50, start: 0.000000, bitrate: 846 kb/s<br />
    Stream #0:0(eng): Video: h264 (High), yuv420p, 720x404, SAR 1:1 DAR 180:101, 25 fps<br />
[libvpx-vp9 @ 0x20da340] v1.2.0-2099-gb4e3909<br />
Output #0, matroska, to 'out2.mkv':<br />
    Stream #0:0(eng): Video: vp9 (libvpx-vp9) ([255][255][255][255] / 0xFFFFFFFF), yuv420p, 720x404 [SAR 1:1 DAR 180:101], q=-1--1, pass 2, 600 kb/s, 1k tbn, 25 tbc (default)</p>
<p>frame=  748 fps=1.9 q=0.0 Lsize=    2193kB time=00:00:30.00 bitrate= 598.9kbits/s<br />
video:2187kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.282936%</p>
<p>real    6m31.734s<br />
</code></p>
<p>Seriamente?!<br />
<strong>Un codec che per comprimere 30 secondi di un video 720&#215;404<br />
ci mette 6 minuti e 50 secondi (prima + seconda passata)?!</strong></p>
<p>Per vedere il video codificato VP9 per ora l&#8217;unico modo è usare ffplay compilato con ffmpeg:</p>
<p><code>./ffplay-vp9 out.mkv -strict -2</code></p>
<p>La qualità non mi sembra nulla di speciale, potrei anche aspettare giorni di compressione per ottenere un video HD eccezionale a bitrate bassissimo, ma non è SICURAMENTE il caso di VP9, che è <strong>SOLO MOLTO MOLTO MOLTO LENTO</strong>.</p>
<p>Testato anche l&#8217;encoder <em>vpxenc</em> della libvpx, stessi risultati &#8220;diludenti&#8221;.</p>
<p>Meno male che è QUASI pronto &#8230;</p>
<p><strong>Stesso test con VP8</strong><br />
<code><br />
time ./ffmpeg-vp9 -y -i /home/mc/test.mkv -t 00:00:30  -c:v libvpx -quality good -b:v 600k -speed 16 -rc_lookahead 25 -pass 1 -an -f matroska  /dev/null</p>
<p>frame=  748 fps= 79 q=0.0 Lsize=       1kB time=00:00:00.00 bitrate=N/A<br />
video:0kB audio:0kB subtitle:0 global headers:0kB muxing overhead inf%</p>
<p>real    0m9.555s<br />
</code></p>
<p><strong>VP8 pass2</strong><br />
<code><br />
time ./ffmpeg-vp9 -y -i /home/mc/test.mkv -t 00:00:30  -c:v libvpx -quality good -b:v 600k -speed 16 -rc_lookahead 25 -pass 2 -an -f matroska  out3.mkv</p>
<p>frame=  748 fps=106 q=0.0 Lsize=    2201kB time=00:00:30.00 bitrate= 601.0kbits/s<br />
video:2195kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.282946%</p>
<p>real    0m7.120s<br />
</code></p>
<p><strong>Circa 16 secondi per le due passate con VP8.</p>
<p>Stesso test con x264 profilo baseline. </strong><br />
<code><br />
time ./ffmpeg-vp9 -y -i /home/mc/test.mkv -t 00:00:30  -c:v libx264 -profile baseline -b:v 600k -pass 1 -an -f matroska  /dev/null</p>
<p>frame=  748 fps=290 q=-1.0 Lsize=    2229kB time=00:00:30.00 bitrate= 608.6kbits/s<br />
video:2223kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.279619%</p>
<p>real    0m2.652s<br />
</code></p>
<p><strong>x264 pass2</strong><br />
<code><br />
time ./ffmpeg-vp9 -y -i /home/mc/test.mkv -t 00:00:30  -c:v libx264 -profile baseline -b:v 600k -pass 2 -an -f matroska  out4.mkv</p>
<p>frame=  748 fps=147 q=-1.0 Lsize=    2219kB time=00:00:30.00 bitrate= 605.9kbits/s<br />
video:2213kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.280793%</p>
<p>real    0m5.195s<br />
</code></p>
<p><strong>Circa 8 secondi per x264.</strong></p>
<p>Aspettiamo la futura implementazione free di un codec h265,<br />
per vedere le potenzialitò di HEVC.</p>
<p><strong>VP9 è &#8220;un treno di diludendo&#8221; (cit.) </strong></p>
<p> <a href="http://forum.doom9.org/showthread.php?t=165839" target="_blank">Discussione su Doom9</a></p>
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		<title>FFmpeg, OpenCL sui filtri deshake e unsharp, test.</title>
		<link>http://telperion.wordpress.com/2013/05/09/ffmpeg-opencl-sui-filtri-deshake-e-unsharp-test/</link>
		<comments>http://telperion.wordpress.com/2013/05/09/ffmpeg-opencl-sui-filtri-deshake-e-unsharp-test/#comments</comments>
		<pubDate>Thu, 09 May 2013 13:30:28 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

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		<description><![CDATA[Oltre a x264, anche ffmpeg 1.2+git ha incluso l&#8217;accelerazione OpenCL, per ora su due filtri deshake e unsharp. Info sui commit qui. Vediamo il test su Debian sid 64, CPU Intel Q8300, GPU NVIDIA GT 440. Deshake senza OpenCL. ~time ffmpeg -y -i /media/scambio/Amazing_Caves_1080.wmv \ -vf deshake=opencl=0 \ -threads 0 -c:v libx264 \ -preset fast [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3161&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>Oltre a <a href="http://telperion.wordpress.com/2013/05/09/x264-opencl-lookahead-test/" target="_blank">x264</a>, anche ffmpeg 1.2+git ha incluso l&#8217;accelerazione OpenCL,<br />
per ora su due filtri <strong><a href="http://www.ffmpeg.org/ffmpeg-filters.html#deshake" target="_blank">deshake</a></strong> e <strong><a href="http://www.ffmpeg.org/ffmpeg-filters.html#unsharp" target="_blank">unsharp</a></strong>.</p>
<p>Info <a href="http://git.videolan.org/?p=ffmpeg.git&amp;a=search&amp;h=HEAD&amp;st=commit&amp;s=opencl" target="_blank">sui commit qui</a>.</p>
<p>Vediamo il test su Debian sid 64, CPU Intel Q8300, GPU NVIDIA GT 440.</p>
<p><span id="more-3161"></span></p>
<p><strong>Deshake senza OpenCL.</strong></p>
<p><code>~time ffmpeg -y -i /media/scambio/Amazing_Caves_1080.wmv \<br />
-vf deshake=opencl=0 \<br />
-threads 0 -c:v libx264 \<br />
-preset fast -tune film -an \<br />
-f matroska -b:v 1800k video.mkv</p>
<p>ffmpeg version N-52849-gacc4a7e Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May  7 2013 14:10:09 with gcc 4.7 (Debian 4.7.2-5)</p>
<p>Input #0, asf, from '/media/scambio/Amazing_Caves_1080.wmv':<br />
  Duration: 00:01:25.50, start: 0.000000, bitrate: 8295 kb/s</p>
<p>[libx264 @ 0x1c6a580] using SAR=4/3<br />
[libx264 @ 0x1c6a580] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x1c6a580] profile High, level 4.0</p>
<p>Stream mapping:<br />
  Stream #0:1 -&gt; #0:0 (wmv3 -&gt; libx264)<br />
Press [q] to stop, [?] for help<br />
frame= 2037 fps=7.9 q=-1.0 Lsize=   17159kB time=00:01:24.87 bitrate=1656.1kbits/s<br />
video:17143kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.091572%</p>
<p>real    4m19.541s</code></p>
<p><strong>Deshake con OpenCL.</strong></p>
<p><code>~time ffmpeg -y -i /media/scambio/Amazing_Caves_1080.wmv \<br />
-vf deshake=opencl=1 \<br />
-threads 0 -c:v libx264 \<br />
-preset fast -tune film -an \<br />
-f matroska -b:v 1800k video.mkv</p>
<p>ffmpeg version N-52849-gacc4a7e Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May  7 2013 14:10:09 with gcc 4.7 (Debian 4.7.2-5)</p>
<p>Input #0, asf, from '/media/scambio/Amazing_Caves_1080.wmv':<br />
  Duration: 00:01:25.50, start: 0.000000, bitrate: 8295 kb/s</p>
<p>[libx264 @ 0x1d4f580] using SAR=4/3<br />
[libx264 @ 0x1d4f580] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x1d4f580] profile High, level 4.0</p>
<p>Stream mapping:<br />
  Stream #0:1 -&gt; #0:0 (wmv3 -&gt; libx264)<br />
Press [q] to stop, [?] for help<br />
frame= 2037 fps= 15 q=-1.0 Lsize=   17158kB time=00:01:24.87 bitrate=1656.1kbits/s<br />
video:17143kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.091568%</p>
<p>real    2m12.312s</code></p>
<p><strong>Unsharp senza OpenCL.</strong></p>
<p><code>~time ffmpeg -y -i /media/scambio/Amazing_Caves_1080.wmv \<br />
-vf unsharp=opencl=0 \<br />
-threads 0 -c:v libx264 \<br />
-preset fast -tune film -an \<br />
-f matroska -b:v 1800k video.mkv</p>
<p>ffmpeg version N-52849-gacc4a7e Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May  7 2013 14:10:09 with gcc 4.7 (Debian 4.7.2-5)</p>
<p>Input #0, asf, from '/media/scambio/Amazing_Caves_1080.wmv':<br />
  Duration: 00:01:25.50, start: 0.000000, bitrate: 8295 kb/s</p>
<p>[libx264 @ 0x18be580] using SAR=4/3<br />
[libx264 @ 0x18be580] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x18be580] profile High, level 4.0</p>
<p>Stream mapping:<br />
  Stream #0:1 -&gt; #0:0 (wmv3 -&gt; libx264)<br />
Press [q] to stop, [?] for help<br />
frame= 2037 fps= 23 q=-1.0 Lsize=   17035kB time=00:01:24.87 bitrate=1644.2kbits/s<br />
video:17020kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.092012%</p>
<p>real    1m28.516s</code></p>
<p><strong>Unsharp con OpenCL.</strong></p>
<p><code>~time ffmpeg -y -i /media/scambio/Amazing_Caves_1080.wmv \<br />
-vf unsharp=opencl=1 \<br />
-threads 0 -c:v libx264 \<br />
-preset fast -tune film -an \<br />
-f matroska -b:v 1800k video.mkv</p>
<p>ffmpeg version N-52849-gacc4a7e Copyright (c) 2000-2013 the FFmpeg developers<br />
  built on May  7 2013 14:10:09 with gcc 4.7 (Debian 4.7.2-5)</p>
<p>Input #0, asf, from '/media/scambio/Amazing_Caves_1080.wmv':<br />
  Duration: 00:01:25.50, start: 0.000000, bitrate: 8295 kb/s</p>
<p>[libx264 @ 0x2f9c580] using SAR=4/3<br />
[libx264 @ 0x2f9c580] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
[libx264 @ 0x2f9c580] profile High, level 4.0</p>
<p>Stream mapping:<br />
  Stream #0:1 -&gt; #0:0 (wmv3 -&gt; libx264)<br />
Press [q] to stop, [?] for help<br />
frame= 2037 fps= 23 q=-1.0 Lsize=   17035kB time=00:01:24.87 bitrate=1644.2kbits/s<br />
video:17020kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.092012%</p>
<p>real    1m29.834s</code></p>
<p>Risultati controversi,<br />
accelerazione quasi del 100% sullo stabilizzatore deskake,<br />
mentre il più utile unsharp è anche leggermente più lento con OpenGL.<br />
Mah.</p>
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		<title>x264 OpenCL lookahead, test.</title>
		<link>http://telperion.wordpress.com/2013/05/09/x264-opencl-lookahead-test/</link>
		<comments>http://telperion.wordpress.com/2013/05/09/x264-opencl-lookahead-test/#comments</comments>
		<pubDate>Thu, 09 May 2013 12:39:39 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3155</guid>
		<description><![CDATA[Dal 21 febbraio è stato aggiunto a x264 il supporto OpenCl per lookahead. Per i dettagli leggete qui. Ho voluto fare qualche test su Debian sid 64, CPU Intel Q8300, GPU NVIDIA GT 440. Versione x264-76a5c3a Uploaded with ImageShack.us Per attivare la compilazione di x264 con le librerie OpenCl su linux, è necessario modificare il [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3155&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>Dal 21 febbraio è stato aggiunto a x264 il supporto OpenCl per lookahead.<br />
Per i dettagli <strong><a href="http://git.videolan.org/?p=x264.git;a=commit;h=3a5f6c0aeacfcb21e7853ab4879f23ec8ae5e042" target="_blank">leggete qui</a></strong>.</p>
<p>Ho voluto fare qualche test su Debian sid 64, CPU Intel Q8300, GPU NVIDIA GT 440.<br />
Versione x264-76a5c3a</p>
<p><a target='_blank' title='ImageShack - Image And Video Hosting' href='http://imageshack.us/photo/my-images/341/x264opcl.jpg/'><img src='http://img341.imageshack.us/img341/2952/x264opcl.jpg' border='0' /></a><br />Uploaded with <a target='_blank' href='http://imageshack.us'>ImageShack.us</a></p>
<p><span id="more-3155"></span></p>
<p>Per attivare la compilazione di x264 con le librerie OpenCl su linux,<br />
<strong>è necessario modificare il configure:</strong></p>
<p><code>--- a/configure   2013-04-29 21:29:38.000000000 +0200<br />
+++ b/configure      2013-05-02 16:11:24.000000000 +0200<br />
@@ -1115,8 +1115,8 @@<br />
     # OpenCL support is only well tested on Windows/MinGW.  If you<br />
     # wish to try it on an unsupported platform, swap the lines<br />
     # below.  If OpenCL breaks, you get to keep both halves<br />
-    #opencl="yes"<br />
-    opencl="no"<br />
+    opencl="yes"<br />
+    #opencl="no"<br />
 fi<br />
 if [ "$opencl" = "yes" ]; then<br />
     log_check "looking for perl"<br />
@@ -1125,7 +1125,7 @@<br />
         echo 'OpenCL support requires perl to compile.'<br />
         echo 'use --disable-opencl to compile without OpenCL.'<br />
         exit 1<br />
-    elif [[ $cross_prefix != ""  &amp;&amp;  $host_os == mingw* ]] ; then<br />
+    elif [[ $host_os != mingw* ]] ; then<br />
         if cc_check "CL/cl.h" "-lOpenCL"; then<br />
             echo 'HAVE_OPENCL=yes' &gt;&gt; config.mak<br />
             echo 'OPENCL_LIB=OpenCL' &gt;&gt; config.mak<br />
</code></p>
<p><strong>configurazione di x264:</strong></p>
<p><code>./configure \<br />
--extra-cflags='-g -O3 -mtune=core2 -fstack-protector \<br />
--param=ssp-buffer-size=4 -Wformat -Werror=format-security' \<br />
--extra-ldflags='-Wl,-z,relro' \<br />
--enable-static \<br />
--enable-pic \<br />
--enable-visualize</code></p>
<p><strong>codifica normale:</strong></p>
<p><code>~./x264 --threads 0 --sar 4:3  --bitrate 1800 \<br />
--preset fast --tune film \<br />
-o video.mkv /media/scambio/Amazing_Caves_1080.wmv<br />
lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: profile High, level 4.0<br />
x264 [info]: frame I:14    Avg QP:23.15  size: 85538<br />
x264 [info]: frame P:1211  Avg QP:26.11  size: 11441<br />
x264 [info]: frame B:812   Avg QP:29.11  size:  2906<br />
x264 [info]: consecutive B-frames: 36.3% 24.8% 20.2% 18.7%<br />
x264 [info]: kb/s:1640.28</p>
<p>encoded 2037 frames, 24.73 fps, 1640.35 kb/s</p>
<p>real    1m22.482s</code></p>
<p><strong>codifica con OpenCl:</strong></p>
<p><code>~./x264 --threads 0 --opencl --sar 4:3  --bitrate 1800 \<br />
--preset fast --tune film \<br />
-o video.mkv /media/scambio/Amazing_Caves_1080.wmv<br />
lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: OpenCL acceleration enabled with NVIDIA Corporation GeForce GT 440<br />
x264 [info]: profile High, level 4.0<br />
x264 [info]: frame I:14    Avg QP:23.02  size: 83283<br />
x264 [info]: frame P:1138  Avg QP:26.42  size: 11898<br />
x264 [info]: frame B:885   Avg QP:28.41  size:  3023<br />
x264 [info]: consecutive B-frames: 29.6% 31.2% 19.0% 20.2%<br />
x264 [info]: kb/s:1637.39</p>
<p>encoded 2037 frames, 25.49 fps, 1637.46 kb/s</p>
<p>real    1m20.106s</code></p>
<p><strong>Ho fatto anche un test di codifica a 10Bit, con x264 configurato con:</strong></p>
<p><code>./configure \<br />
--extra-cflags='-g -O3 -mtune=core2 -fstack-protector \<br />
--param=ssp-buffer-size=4 -Wformat -Werror=format-security' \<br />
--extra-ldflags='-Wl,-z,relro' \<br />
--enable-static \<br />
--enable-pic \<br />
--bit-depth=10 \<br />
--enable-visualize</code></p>
<p><strong>Codifica a 10 bit:</strong></p>
<p><code>~./x264 --threads 0 --sar 4:3  --bitrate 1800 \<br />
--preset fast --tune film \<br />
-o video.mkv /media/scambio/Amazing_Caves_1080.wmv<br />
lavf [info]: 1440x1080p 0:1 @ 0/0 fps (vfr)<br />
x264 [info]: using SAR=4/3<br />
x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64<br />
x264 [info]: profile High 10, level 4.0, 4:2:0 10-bit<br />
x264 [info]: frame I:14    Avg QP:33.94  size: 96241<br />
x264 [info]: frame P:1455  Avg QP:38.01  size: 10247<br />
x264 [info]: frame B:568   Avg QP:40.87  size:  2154<br />
x264 [info]: consecutive B-frames: 44.7% 54.4%  0.1%  0.8%<br />
x264 [info]: kb/s:1646.68</p>
<p>encoded 2037 frames, 16.36 fps, 1646.75 kb/s</p>
<p>real    2m4.628s</code></p>
<p>Che dire, opencl non mi sembra fornire questa grande accelerazione.</p>
<p><em><strong>&#8220;Mi stai diludendo&#8221; (cit.)</strong></em></p>
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		<title>FFmpeg e vid.stab &#8211; Transcode video stabilization plugin</title>
		<link>http://telperion.wordpress.com/2013/04/25/ffmpeg-e-vid-stab-transcode-video-stabilization-plugin/</link>
		<comments>http://telperion.wordpress.com/2013/04/25/ffmpeg-e-vid-stab-transcode-video-stabilization-plugin/#comments</comments>
		<pubDate>Thu, 25 Apr 2013 14:11:43 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Debian]]></category>
		<category><![CDATA[Video]]></category>

		<guid isPermaLink="false">http://telperion.wordpress.com/?p=3147</guid>
		<description><![CDATA[Ora possiamo usare vid.stab per stabilizzare i nostri video ballerini anche con ffmpeg. Home vid.stab e video demo. Ovviamente per usarlo con ffmpeg occorre la libreria libvidstab (su debian sid non c&#8217;è, l&#8217;ho impacchettata da me), e compilare il git di ffmpeg con --enable-libvidstab git libvidstab I filtri da usare (in 2 passate) sono: vidstabdetect [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3147&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>Ora possiamo usare vid.stab per stabilizzare i nostri video ballerini anche con ffmpeg.</p>
<p><a href="http://public.hronopik.de/vid.stab/" target="_blank">Home vid.stab e <strong>video demo</strong>.</a></p>
<p><span class='embed-youtube' style='text-align:center; display: block;'><iframe class='youtube-player' type='text/html' width='640' height='390' src='http://www.youtube.com/embed/HYE3KAl8RAQ?version=3&#038;rel=1&#038;fs=1&#038;showsearch=0&#038;showinfo=1&#038;iv_load_policy=1&#038;wmode=transparent' frameborder='0'></iframe></span></p>
<p>Ovviamente per usarlo con ffmpeg occorre la libreria libvidstab (su debian sid non c&#8217;è, l&#8217;ho impacchettata da me), e compilare il git di ffmpeg con   <code>--enable-libvidstab</code> </p>
<p><a href="https://github.com/georgmartius/vid.stab" target="_blank">git libvidstab</a></p>
<p>I filtri da usare (in 2 passate) sono:</p>
<p><a href="http://www.ffmpeg.org/ffmpeg-filters.html#vidstabdetect" target="_blank"><strong>vidstabdetect</strong></a></p>
<p><a href="http://www.ffmpeg.org/ffmpeg-filters.html#vidstabtransform" target="_blank"><strong>vidstabtransform</strong></a></p>
<p>Help:</p>
<p><code>ffmpeg -h filter=vidstabdetect</code><br />
<code>ffmpeg -h filter=vidstabtransform</code></p>
<p>Altro stabilizzatore video presente in ffmpeg è <a href="http://www.ffmpeg.org/ffmpeg-filters.html#deshake" target="_blank"><strong>deshake</strong></a> abilitato anche ad usare l&#8217;accelerazione hardware opencl.</p>
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		<title>FFmpeg: concatenare (unire) più video col filtro concat</title>
		<link>http://telperion.wordpress.com/2013/04/13/ffmpeg-concatenare-piu-video-col-filtro-concat/</link>
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		<pubDate>Sat, 13 Apr 2013 14:54:45 +0000</pubDate>
		<dc:creator>telperion</dc:creator>
				<category><![CDATA[Video]]></category>

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		<description><![CDATA[FFmpeg dalla versione 1.1 include il filtro concat (oltre al protocollo ed al demuxer concat) che permette di unire diversi file video non omogenei, scalandoli ed applicando vari filtri (rumore, deinterlacciamento eccetera), e ricodificando il tutto in un file finale. Esempio: ffmpeg -f lavfi -i \ " \ movie=1.mp4, scale=640:360,setdar=16/9,hqdn3d=4 [v1] ; amovie=1.mp4 [a1] ; [&#8230;]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=telperion.wordpress.com&#038;blog=364810&#038;post=3140&#038;subd=telperion&#038;ref=&#038;feed=1" width="1" height="1" />]]></description>
				<content:encoded><![CDATA[<p>FFmpeg dalla versione 1.1 include <strong>il filtro concat</strong> (oltre al protocollo ed al demuxer concat)<br />
che permette di unire diversi file video non omogenei, scalandoli ed applicando vari filtri (rumore, deinterlacciamento eccetera), e ricodificando il tutto in un file finale.</p>
<p><span id="more-3140"></span><br />
Esempio:</p>
<p><code><br />
ffmpeg -f lavfi -i \<br />
" \<br />
movie=1.mp4, scale=640:360,setdar=16/9,hqdn3d=4 [v1] ; amovie=1.mp4 [a1] ; \<br />
movie=2.avi, scale=640:360,setdar=16/9 [v2] ; amovie=2.avi [a2] ; \<br />
movie=3.flv, scale=640:360,setdar=16/9 [v3] ; amovie=3.flv [a3] ; \<br />
[v1] [v2] [v3] concat=n=3 [out0] ; \<br />
[a1] [a2] [a3] concat=n=3:v=0:a=1 [out1] \<br />
" \<br />
-threads 4 -c:v libx264 -preset faster -tune film \<br />
-x264opts ref=4:bframes=4:direct=auto:aq-strength=1.3 \<br />
-c:a libaacplus -b:a 32k -ar 48k -ac 2 -f matroska \<br />
-ar 48k -ac 2 -b:a 32k -b:v 900k out.mkv</code></p>
<p>Se invece dovete unire più video omogenei (stesse dimensioni e codec) senza ricodifica,<br />
potete usare <strong>il demuxer concat</strong> creando un file</p>
<p>lista.txt</p>
<p>contenente</p>
<p><code># this is a comment<br />
file '/path/to/file1'<br />
file '/path/to/file2'<br />
file '/path/to/file3'</code></p>
<p>e poi eseguite:</p>
<p><code>ffmpeg -f concat -i lista.txt -c copy output</code></p>
<p>esempio:<br />
lista.txt</p>
<p><code># commento<br />
file 1.avi<br />
file 2.avi<br />
file 3.avi</code></p>
<p>e poi</p>
<p><code>ffmpeg -f concat -i lista.txt -c copy out.avi</code></p>
<p><strong><a href="http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20concatenate%20%28join,%20merge%29%20media%20files" target="_blank">Maggiori info qui.</a></strong></p>
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