[FFmpeg-trac] #2299(FFmpeg:new): -dump_attachment option is poorly documented and/or doesn't work
FFmpeg
trac at avcodec.org
Sat Feb 23 15:55:32 CET 2013
#2299: -dump_attachment option is poorly documented and/or doesn't work
--------------------------------+--------------------------------------
Reporter: slhck | Type: defect
Status: new | Priority: normal
Component: FFmpeg | Version: git-master
Keywords: | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
--------------------------------+--------------------------------------
The FFmpeg documentation gives the following example for dumping
attachments from MKV files:
{{{
To extract all attachments to files determined by the filename tag:
ffmpeg -dump_attachment:t "" INPUT
}}}
There are a few confusing points about this example:
* {{{-dump_attachment}}} seems to be a per-file option, and not a global
one, so it should come _after_ the input.
* The input file would be missing the {{{-i}}} option altogether
Because of this, FFmpeg just overwrites and empties the input file when
using the above command.
Here's an example with an attachment created with {{{mkvmerge}}}:
{{{
mkvmerge -o out.mkv -A in.mp4 \
--attachment-description "Test Attachment" \
--attachment-mime-type image/jpeg \
--attach-file out.jpg
mkvmerge v5.0.1 ('Es ist Sommer') built on Jul 30 2012 19:32:42
'in.mp4': Using the Quicktime/MP4 demultiplexer.
'in.mp4' track 1: Using the MPEG-4 part 10 (AVC) video output module.
The file 'out.mkv' has been opened for writing.
'in.mp4' track 1: Extracted the aspect ratio information from the MPEG-4
layer 10 (AVC) video data and set the display dimensions to 1280/720.
Progress: 100%
The cue entries (the index) are being written...
Muxing took 0 seconds.
}}}
Checking whether the file really contains an attachment:
{{{
mkvmerge -i out.mkv
File 'out.mkv': container: Matroska
Track ID 1: video (V_MPEG4/ISO/AVC)
Attachment ID 1: type 'image/jpeg', size 45690 bytes, description 'Test
Attachment', file name 'out.jpg'
}}}
Then, with FFmpeg:
{{{
ffmpeg -dump_attachment:t "" out.mkv
ffmpeg version 1.1.2 Copyright (c) 2000-2013 the FFmpeg developers
built on Feb 8 2013 22:55:29 with Apple LLVM version 4.2
(clang-425.0.24) (based on LLVM 3.2svn)
configuration: --prefix=/usr/local/Cellar/ffmpeg/1.1.2 --enable-shared
--enable-pthreads --enable-gpl --enable-version3 --enable-nonfree
--enable-hardcoded-tables --enable-avresample --cc=cc --host-cflags=
--host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame
--enable-libxvid --enable-libfreetype --enable-libtheora --enable-
libvorbis --enable-libvpx --enable-libopencore-amrnb --enable-libopencore-
amrwb --enable-libvo-aacenc --enable-ffplay --enable-libfdk-aac --enable-
libopus --enable-libopenjpeg --extra-
cflags='-I/usr/local/Cellar/openjpeg/1.5.1/include/openjpeg-1.5 '
libavutil 52. 13.100 / 52. 13.100
libavcodec 54. 86.100 / 54. 86.100
libavformat 54. 59.106 / 54. 59.106
libavdevice 54. 3.102 / 54. 3.102
libavfilter 3. 32.100 / 3. 32.100
libswscale 2. 1.103 / 2. 1.103
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 2.100 / 52. 2.100
File 'out.mkv' already exists. Overwrite ? [y/N]
}}}
Naturally, pressing {{{y}}} here would just overwrite the file and do
nothing.
This also doesn't work, as a per-file option. It doesn't dump the
attachment.
{{{
ffmpeg -i out.mkv -dump_attachment "" -c copy out2.mkv
ffmpeg version 1.1.2 Copyright (c) 2000-2013 the FFmpeg developers
built on Feb 8 2013 22:55:29 with Apple LLVM version 4.2
(clang-425.0.24) (based on LLVM 3.2svn)
configuration: --prefix=/usr/local/Cellar/ffmpeg/1.1.2 --enable-shared
--enable-pthreads --enable-gpl --enable-version3 --enable-nonfree
--enable-hardcoded-tables --enable-avresample --cc=cc --host-cflags=
--host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame
--enable-libxvid --enable-libfreetype --enable-libtheora --enable-
libvorbis --enable-libvpx --enable-libopencore-amrnb --enable-libopencore-
amrwb --enable-libvo-aacenc --enable-ffplay --enable-libfdk-aac --enable-
libopus --enable-libopenjpeg --extra-
cflags='-I/usr/local/Cellar/openjpeg/1.5.1/include/openjpeg-1.5 '
libavutil 52. 13.100 / 52. 13.100
libavcodec 54. 86.100 / 54. 86.100
libavformat 54. 59.106 / 54. 59.106
libavdevice 54. 3.102 / 54. 3.102
libavfilter 3. 32.100 / 3. 32.100
libswscale 2. 1.103 / 2. 1.103
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 2.100 / 52. 2.100
Input #0, matroska,webm, from 'out.mkv':
Metadata:
creation_time : 2013-02-23 14:22:56
Duration: 00:03:31.48, start: 0.000000, bitrate: 2232 kb/s
Stream #0:0(eng): Video: h264 (High), yuv420p, 1280x720 [SAR 1:1 DAR
16:9], 25 fps, 25 tbr, 1k tbn, 50 tbc (default)
Stream #0:1: Attachment: mjpeg
Metadata:
filename : out.jpg
mimetype : image/jpeg
Output #0, matroska, to 'out2.mkv':
Metadata:
encoder : Lavf54.59.106
Stream #0:0(eng): Video: h264 (H264 / 0x34363248), yuv420p, 1280x720
[SAR 1:1 DAR 16:9], q=2-31, 25 fps, 1k tbn, 1k tbc (default)
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
frame= 5287 fps=0.0 q=-1.0 Lsize= 57601kB time=00:03:31.36
bitrate=2232.5kbits/s
video:57559kB audio:0kB subtitle:0 global headers:0kB muxing overhead
0.071764%
}}}
Note:
* In the above examples, substituting {{{-dump_attachment:t}}} for
{{{-dump_attachment}}} doesn't make a difference.
* The defect is the same in the Git master head.
--
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2299>
FFmpeg <http://ffmpeg.org>
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