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Richard Stallman et le logiciel libre
19 octobre 2011, par
Mis à jour : Mai 2013
Langue : français
Type : Texte
Autres articles (45)
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Keeping control of your media in your hands
13 avril 2011, parThe vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...) -
Le plugin : Podcasts.
14 juillet 2010, parLe problème du podcasting est à nouveau un problème révélateur de la normalisation des transports de données sur Internet.
Deux formats intéressants existent : Celui développé par Apple, très axé sur l’utilisation d’iTunes dont la SPEC est ici ; Le format "Media RSS Module" qui est plus "libre" notamment soutenu par Yahoo et le logiciel Miro ;
Types de fichiers supportés dans les flux
Le format d’Apple n’autorise que les formats suivants dans ses flux : .mp3 audio/mpeg .m4a audio/x-m4a .mp4 (...) -
Les images
15 mai 2013
Sur d’autres sites (4714)
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ffmpeg seek calculating wrong byte range ?
17 décembre 2015, par user4455I’m running into an issue while trying to extract thumbnails from a movie file at a specific timestamp. Generally I’ve had no issues with this, but I’ve come across a set of movie files that are getting an error about the byte range requested (416 Requested Range Not Satisfiable).
The odd thing is that the server is correctly returning the content length in the partial content request, yet when it requests the movie file it requests a length that exceeds that.
This is a bit over my head, so I’m not sure what could be happening here. Any insight would be great.
The Command :
/usr/bin/ffmpeg -y -ss 1400 -i 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4' -qscale:v 2 -f image2 -vframes 1 -filter:v 'scale=192:108' -loglevel debug /data/www/storage/test.jpg 2>&1
The Error :
[https @ 0x22e1e00] header='HTTP/1.1 416 Requested Range Not Satisfiable'
[https @ 0x22e1e00] http_code=416
[https @ 0x22e1e00] HTTP error 416 Requested Range Not SatisfiableSource File Size :
1776706045 bytes
Source Content Duration :
2897.624271
Partial Content Request :
[https @ 0x22e1e00] header='HTTP/1.1 206 Partial Content'
[https @ 0x22e1e00] http_code=206
[https @ 0x22e1e00] header='x-amz-id-2: 4J1pgHExIUA0GxIxSBmGJjrRqliHbsIjXeuGzVfTlaaoVXbyZI5FQNma8fGaifcovkXfxJev5yU='
[https @ 0x22e1e00] header='x-amz-request-id: 78B3BDBB0356EF40'
[https @ 0x22e1e00] header='Date: Wed, 16 Dec 2015 23:51:29 GMT'
[https @ 0x22e1e00] header='x-amz-meta-content-length: 2898'
[https @ 0x22e1e00] header='x-amz-meta-cb-modifiedtime: Tue, 15 Dec 2015 17:59:51 GMT'
[https @ 0x22e1e00] header='Last-Modified: Wed, 16 Dec 2015 23:44:59 GMT'
[https @ 0x22e1e00] header='ETag: "6341a8022630667a8070a83575e542e7-27"'
[https @ 0x22e1e00] header='Accept-Ranges: bytes'
[https @ 0x22e1e00] header='Content-Range: bytes 0-1776706044/1776706045'
[https @ 0x22e1e00] header='Content-Type: video/mp4'
[https @ 0x22e1e00] header='Content-Length: 1776706045'
[https @ 0x22e1e00] header='Server: AmazonS3'
[https @ 0x22e1e00] header='Connection: close'FFmpeg Request :
request: GET /my-bucket/mymoviefile.mp4 HTTP/1.1
User-Agent: Lavf/56.25.101
Accept: */*
Range: bytes=1781732960-
Connection: close
Host: s3-us-west-2.amazonaws.com
Icy-MetaData: 1Entire Log :
# /usr/bin/ffmpeg -y -ss 1400 -i 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4' -qscale:v 2 -f image2 -vframes 1 -filter:v 'scale=192:108' -loglevel debug /data/www/storage/test.jpg 2>&1
ffmpeg version 2.6.4 Copyright (c) 2000-2015 the FFmpeg developers
built with gcc 4.9.2 (Debian 4.9.2-10)
configuration: --prefix=/usr --extra-cflags='-g -O2 -fstack-protector-strong -Wformat -Werror=format-security ' --extra-ldflags='-Wl,-z,relro' --cc='ccache cc' --enable-shared --enable-libmp3lame --enable-gpl --enable-nonfree --enable-libvorbis --enable-pthreads --enable-libfaac --enable-libxvid --enable-postproc --enable-x11grab --enable-libgsm --enable-libtheora --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libspeex --enable-nonfree --disable-stripping --enable-libvpx --enable-libschroedinger --disable-encoder=libschroedinger --enable-version3 --enable-libopenjpeg --enable-librtmp --enable-avfilter --enable-libfreetype --enable-libvo-aacenc --disable-decoder=amrnb --enable-libvo-amrwbenc --enable-libaacplus --libdir=/usr/lib/x86_64-linux-gnu --disable-vda --enable-libbluray --enable-libcdio --enable-gnutls --enable-frei0r --enable-openssl --enable-libass --enable-libopus --enable-fontconfig --enable-libpulse --disable-mips32r2 --disable-mipsdspr1 --disable-mipsdspr2 --enable-libvidstab --enable-libzvbi --enable-avresample --disable-htmlpages --disable-podpages --enable-libutvideo --enable-libfdk-aac --enable-libx265 --enable-libiec61883 --enable-vaapi --enable-libdc1394 --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
libavutil 54. 20.100 / 54. 20.100
libavcodec 56. 26.100 / 56. 26.100
libavformat 56. 25.101 / 56. 25.101
libavdevice 56. 4.100 / 56. 4.100
libavfilter 5. 11.102 / 5. 11.102
libavresample 2. 1. 0 / 2. 1. 0
libswscale 3. 1.101 / 3. 1.101
libswresample 1. 1.100 / 1. 1.100
libpostproc 53. 3.100 / 53. 3.100
Splitting the commandline.
Reading option '-y' ... matched as option 'y' (overwrite output files) with argument '1'.
Reading option '-ss' ... matched as option 'ss' (set the start time offset) with argument '1400'.
Reading option '-i' ... matched as input file with argument 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4'.
Reading option '-qscale:v' ... matched as option 'qscale' (use fixed quality scale (VBR)) with argument '2'.
Reading option '-f' ... matched as option 'f' (force format) with argument 'image2'.
Reading option '-vframes' ... matched as option 'vframes' (set the number of video frames to output) with argument '1'.
Reading option '-filter:v' ... matched as option 'filter' (set stream filtergraph) with argument 'scale=192:108'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument 'debug'.
Reading option '/data/www/storage/test.jpg' ... matched as output file.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option y (overwrite output files) with argument 1.
Applying option loglevel (set logging level) with argument debug.
Successfully parsed a group of options.
Parsing a group of options: input file https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4.
Applying option ss (set the start time offset) with argument 1400.
Successfully parsed a group of options.
Opening an input file: https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4.
[https @ 0x22e1e00] request: GET /my-bucket/mymoviefile.mp4 HTTP/1.1
User-Agent: Lavf/56.25.101
Accept: */*
Range: bytes=0-
Connection: close
Host: s3-us-west-2.amazonaws.com
Icy-MetaData: 1
[https @ 0x22e1e00] header='HTTP/1.1 206 Partial Content'
[https @ 0x22e1e00] http_code=206
[https @ 0x22e1e00] header='x-amz-id-2: 4J1pgHExIUA0GxIxSBmGJjrRqliHbsIjXeuGzVfTlaaoVXbyZI5FQNma8fGaifcovkXfxJev5yU='
[https @ 0x22e1e00] header='x-amz-request-id: 78B3BDBB0356EF40'
[https @ 0x22e1e00] header='Date: Wed, 16 Dec 2015 23:51:29 GMT'
[https @ 0x22e1e00] header='x-amz-meta-content-length: 2898'
[https @ 0x22e1e00] header='x-amz-meta-cb-modifiedtime: Tue, 15 Dec 2015 17:59:51 GMT'
[https @ 0x22e1e00] header='Last-Modified: Wed, 16 Dec 2015 23:44:59 GMT'
[https @ 0x22e1e00] header='ETag: "6341a8022630667a8070a83575e542e7-27"'
[https @ 0x22e1e00] header='Accept-Ranges: bytes'
[https @ 0x22e1e00] header='Content-Range: bytes 0-1776706044/1776706045'
[https @ 0x22e1e00] header='Content-Type: video/mp4'
[https @ 0x22e1e00] header='Content-Length: 1776706045'
[https @ 0x22e1e00] header='Server: AmazonS3'
[https @ 0x22e1e00] header='Connection: close'
[https @ 0x22e1e00] header=''
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] Format mov,mp4,m4a,3gp,3g2,mj2 probed with size=2048 and score=100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] ISO: File Type Major Brand: mp42
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] Before avformat_find_stream_info() pos: 1647960 bytes read:1652200 seeks:0
[h264 @ 0x22e92c0] no picture
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] All info found
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] After avformat_find_stream_info() pos: 1862326 bytes read:1878504 seeks:0 frames:16
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: isommp41avc1
creation_time : 2015-11-18 02:34:41
Duration: 00:48:17.70, start: 0.000000, bitrate: 4905 kb/s
Stream #0:0(und), 15, 1/2997: Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, left), 1920x1080 (1920x1088) [SAR 1:1 DAR 16:9], 1001/60000, 9994 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 59.94 tbc (default)
Metadata:
creation_time : 2015-11-18 02:34:41
handler_name : ?Apple Video Media Handler
Stream #0:1(und), 1, 1/48000: Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
creation_time : 2015-11-18 02:34:41
handler_name : ?Apple Sound Media Handler
Successfully opened the file.
Parsing a group of options: output file /data/www/storage/test.jpg.
Applying option qscale:v (use fixed quality scale (VBR)) with argument 2.
Applying option f (force format) with argument image2.
Applying option vframes (set the number of video frames to output) with argument 1.
Applying option filter:v (set stream filtergraph) with argument scale=192:108.
Successfully parsed a group of options.
Opening an output file: /data/www/storage/test.jpg.
Successfully opened the file.
detected 2 logical cores
[Parsed_scale_0 @ 0x22cd4c0] Setting 'w' to value '192'
[Parsed_scale_0 @ 0x22cd4c0] Setting 'h' to value '108'
[Parsed_scale_0 @ 0x22cd4c0] Setting 'flags' to value '0x4'
[Parsed_scale_0 @ 0x22cd4c0] w:192 h:108 flags:'0x4' interl:0
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'video_size' to value '1920x1080'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'pix_fmt' to value '0'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'time_base' to value '1/2997'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'pixel_aspect' to value '1/1'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'sws_param' to value 'flags=2'
[graph 0 input from stream 0:0 @ 0x22ccfe0] Setting 'frame_rate' to value '2997/100'
[graph 0 input from stream 0:0 @ 0x22ccfe0] w:1920 h:1080 pixfmt:yuv420p tb:1/2997 fr:2997/100 sar:1/1 sws_param:flags=2
[format @ 0x2798640] compat: called with args=[yuvj420p|yuvj422p|yuvj444p]
[format @ 0x2798640] Setting 'pix_fmts' to value 'yuvj420p|yuvj422p|yuvj444p'
[AVFilterGraph @ 0x22cda60] query_formats: 5 queried, 4 merged, 0 already done, 0 delayed
[Parsed_scale_0 @ 0x22cd4c0] picking yuvj420p out of 3 ref:yuv420p alpha:0
[swscaler @ 0x22c3c80] deprecated pixel format used, make sure you did set range correctly
[Parsed_scale_0 @ 0x22cd4c0] w:1920 h:1080 fmt:yuv420p sar:1/1 -> w:192 h:108 fmt:yuvj420p sar:1/1 flags:0x4
[mjpeg @ 0x2854e20] intra_quant_bias = 96 inter_quant_bias = 0
[mjpeg @ 0x28716c0] intra_quant_bias = 96 inter_quant_bias = 0
[mjpeg @ 0x2795320] intra_quant_bias = 96 inter_quant_bias = 0
Output #0, image2, to '/data/www/storage/test.jpg':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: isommp41avc1
encoder : Lavf56.25.101
Stream #0:0(und), 0, 100/2997: Video: mjpeg, yuvj420p(pc, left), 192x108 [SAR 1:1 DAR 16:9], 100/2997, q=2-31, 200 kb/s, 29.97 fps, 29.97 tbn, 29.97 tbc (default)
Metadata:
creation_time : 2015-11-18 02:34:41
handler_name : ?Apple Video Media Handler
encoder : Lavc56.26.100 mjpeg
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
Press [q] to stop, [?] for help
[https @ 0x22e1e00] request: GET /my-bucket/mymoviefile.mp4 HTTP/1.1
User-Agent: Lavf/56.25.101
Accept: */*
Range: bytes=1781732960-
Connection: close
Host: s3-us-west-2.amazonaws.com
Icy-MetaData: 1
[https @ 0x22e1e00] header='HTTP/1.1 416 Requested Range Not Satisfiable'
[https @ 0x22e1e00] http_code=416
[https @ 0x22e1e00] HTTP error 416 Requested Range Not Satisfiable
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x22e1740] stream 0, offset 0x6a331660: partial file
https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4: Invalid data found when processing input
[output stream 0:0 @ 0x22d7500] EOF on sink link output stream 0:0:default.
No more output streams to write to, finishing.
frame= 0 fps=0.0 q=0.0 Lsize=N/A time=00:00:00.00 bitrate=N/A
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Input file #0 (https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4):
Input stream #0:0 (video): 0 packets read (0 bytes); 0 frames decoded;
Input stream #0:1 (audio): 0 packets read (0 bytes);
Total: 0 packets (0 bytes) demuxed
Output file #0 (/data/www/storage/test.jpg):
Output stream #0:0 (video): 0 frames encoded; 0 packets muxed (0 bytes);
Total: 0 packets (0 bytes) muxed
Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
0 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0x27ab100] Statistics: 1878504 bytes read, 0 seeksFFprobe Result :
# /usr/bin/ffprobe -show_format -show_streams -i 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4'
ffprobe version 2.6.4 Copyright (c) 2007-2015 the FFmpeg developers
built with gcc 4.9.2 (Debian 4.9.2-10)
configuration: --prefix=/usr --extra-cflags='-g -O2 -fstack-protector-strong -Wformat -Werror=format-security ' --extra-ldflags='-Wl,-z,relro' --cc='ccache cc' --enable-shared --enable-libmp3lame --enable-gpl --enable-nonfree --enable-libvorbis --enable-pthreads --enable-libfaac --enable-libxvid --enable-postproc --enable-x11grab --enable-libgsm --enable-libtheora --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libspeex --enable-nonfree --disable-stripping --enable-libvpx --enable-libschroedinger --disable-encoder=libschroedinger --enable-version3 --enable-libopenjpeg --enable-librtmp --enable-avfilter --enable-libfreetype --enable-libvo-aacenc --disable-decoder=amrnb --enable-libvo-amrwbenc --enable-libaacplus --libdir=/usr/lib/x86_64-linux-gnu --disable-vda --enable-libbluray --enable-libcdio --enable-gnutls --enable-frei0r --enable-openssl --enable-libass --enable-libopus --enable-fontconfig --enable-libpulse --disable-mips32r2 --disable-mipsdspr1 --disable-mipsdspr2 --enable-libvidstab --enable-libzvbi --enable-avresample --disable-htmlpages --disable-podpages --enable-libutvideo --enable-libfdk-aac --enable-libx265 --enable-libiec61883 --enable-vaapi --enable-libdc1394 --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
libavutil 54. 20.100 / 54. 20.100
libavcodec 56. 26.100 / 56. 26.100
libavformat 56. 25.101 / 56. 25.101
libavdevice 56. 4.100 / 56. 4.100
libavfilter 5. 11.102 / 5. 11.102
libavresample 2. 1. 0 / 2. 1. 0
libswscale 3. 1.101 / 3. 1.101
libswresample 1. 1.100 / 1. 1.100
libpostproc 53. 3.100 / 53. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: isommp41avc1
creation_time : 2015-11-18 02:34:41
Duration: 00:48:17.70, start: 0.000000, bitrate: 4905 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv), 1920x1080 [SAR 1:1 DAR 16:9], 9994 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 59.94 tbc (default)
Metadata:
creation_time : 2015-11-18 02:34:41
handler_name : ?Apple Video Media Handler
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
Metadata:
creation_time : 2015-11-18 02:34:41
handler_name : ?Apple Sound Media Handler
[STREAM]
index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=High
codec_type=video
codec_time_base=1001/60000
codec_tag_string=avc1
codec_tag=0x31637661
width=1920
height=1080
has_b_frames=1
sample_aspect_ratio=1:1
display_aspect_ratio=16:9
pix_fmt=yuv420p
level=40
color_range=tv
color_space=unknown
color_transfer=unknown
color_primaries=unknown
chroma_location=left
timecode=N/A
refs=3
is_avc=1
nal_length_size=4
id=N/A
r_frame_rate=2997/100
avg_frame_rate=2997/100
time_base=1/2997
start_pts=0
start_time=0.000000
duration_ts=8684300
duration=2897.664331
bit_rate=9994429
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=86843
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
TAG:creation_time=2015-11-18 02:34:41
TAG:language=und
TAG:handler_name=Apple Video Media Handler
[/STREAM]
[STREAM]
index=1
codec_name=aac
codec_long_name=AAC (Advanced Audio Coding)
profile=LC
codec_type=audio
codec_time_base=1/48000
codec_tag_string=mp4a
codec_tag=0x6134706d
sample_fmt=fltp
sample_rate=48000
channels=2
channel_layout=stereo
bits_per_sample=0
id=N/A
r_frame_rate=0/0
avg_frame_rate=0/0
time_base=1/48000
start_pts=0
start_time=0.000000
duration_ts=139085965
duration=2897.624271
bit_rate=192002
max_bit_rate=N/A
bits_per_raw_sample=N/A
nb_frames=135828
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
TAG:creation_time=2015-11-18 02:34:41
TAG:language=und
TAG:handler_name=Apple Sound Media Handler
[/STREAM]
[FORMAT]
filename=https://s3-us-west-2.amazonaws.com/my-bucket/mymoviefile.mp4
nb_streams=2
nb_programs=0
format_name=mov,mp4,m4a,3gp,3g2,mj2
format_long_name=QuickTime / MOV
start_time=0.000000
duration=2897.695000
size=1776706045
bit_rate=4905156
probe_score=100
TAG:major_brand=mp42
TAG:minor_version=1
TAG:compatible_brands=isommp41avc1
TAG:creation_time=2015-11-18 02:34:41
[/FORMAT] -
Loop/Batch file for extracting all .aac from .m4a files in folder
29 décembre 2015, par MrDesperateI’m desperate. I need to extract the .aac stream from 1749 .m4a files with ffmpeg, but I can’t get a batch file working for me and it would take years to do it manually. This is what I use for single files : "ffmpeg -i example.m4a -vn -c:a copy example.aac"
I don’t want to convert the files. I only want to extract the .aac audio stream (don’t wanna lose more quality).
"ffmpeg -i *.m4a -vn -c:a copy *.aac" isn’t working and I don’t know how to use for in loops since I’m not a programmer. All loops I found on the internet aren’t working for me.
OS : Windows 7 Professional.
I appreciate every help.
-
Multi core theora encoding
26 octobre 2012, par Jamie TaylorWe convert uploaded video to MP4 and OGV, but while trying to speed up the process we've hit a wall. We found the bottleneck is the OGV encoding, While it might take 5 minutes to convert a 350mb AVI to MP4, it takes roughly 25-30 minutes to convert the same file to OGV.
avconv supports multithreading/multiple cores but it seems that libtheora doesn't, does anyone have any way of encoding over multiple cores ? I found an old mail group which discussed a patch but I can't find much else about it, or if it even still works 5 years on.
So. Is multi-core theora processing possible and what should I use to do it ?
For Reference :
avconv -y -i big_buck_bunny_720p_surround.avi -vcodec libtheora -qscale 10 -bufsize 20M -same_quant -acodec libvorbis -ac 2 -ar 44100 -ab 128k buck.ogv