Opened 11 years ago
Closed 10 years ago
#3678 closed defect (fixed)
Regressions in the video duration/bitrate report
| Reported by: | Nicolas Delvaux | Owned by: | |
|---|---|---|---|
| Priority: | normal | Component: | avcodec |
| Version: | git-master | Keywords: | mpeg2video regression |
| Cc: | Blocked By: | ||
| Blocking: | Reproduced by developer: | yes | |
| Analyzed by developer: | no |
Description
We noticed that, from version n1.1 and on, ffprobe reports wrong video duration/bitrate
for a video file (MXF format).
How to reproduce:
% ffprobe Sample.mxf
tested only on Linux, both 32 and 64bits.
Interestingly, note that it works on the standard avconv of Ubuntu 14.04 (9.13-6:9.13-0ubuntu0.14.04.1). We did not test with others avconv versions.
I attached a small sample from the beginning of our video. The console output of
the git HEAD, n1.1, and n1.0 (which is the last version tested without a problem) is given
below:
HEAD (commit 58632070866a529913355df1d9c7cc71fa91ffde)
ffprobe version N-63469-g5863207 Copyright (c) 2007-2014 the FFmpeg developers
built on May 27 2014 16:20:47 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu9)
configuration:
libavutil 52. 87.100 / 52. 87.100
libavcodec 55. 65.100 / 55. 65.100
libavformat 55. 41.100 / 55. 41.100
libavdevice 55. 13.101 / 55. 13.101
libavfilter 4. 5.100 / 4. 5.100
libswscale 2. 6.100 / 2. 6.100
libswresample 0. 19.100 / 0. 19.100
[mxf @ 0x2252020] Estimating duration from bitrate, this may be inaccurate
Input #0, mxf, from 'Sample.mxf':
Metadata:
uid : 98a72bb5-4bba-e111-92d9-00d0280f7410
generation_uid : aca72bb5-4bba-e111-bc13-00d0280f7410
company_name : Omneon Inc.
product_name : Omneon Media Subsystem
modification_date: 2012-06-19 20:16:52
product_version : 6.3.1.0.release
application_platform: Omneon Media Api (mqx)
product_uid : 00000000-0000-0010-8000-050e0b010602
timecode : 10:00:00:01
Duration: 00:00:00.92, start: 0.000000, bitrate: 9118 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv), 720x608 [SAR 152:135 DAR 4:3], max. 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s24le, 48000 Hz, 8 channels, s32, 9216 kb/s
n1.1
ffprobe version 1.1 Copyright (c) 2007-2013 the FFmpeg developers
built on May 27 2014 16:51:17 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu9)
configuration:
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
Truncating packet of size 250000 to 102381
[mxf @ 0x1711c60] Estimating duration from bitrate, this may be inaccurate
Input #0, mxf, from 'Sample.mxf':
Metadata:
timecode : 10:00:00:01
Duration: 00:00:00.92, start: 0.000000, bitrate: 9118 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 152:135 DAR 4:3], 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s24le, 48000 Hz, 8 channels, s32, 9216 kb/s
n1.0
ffprobe version 1.0 Copyright (c) 2007-2012 the FFmpeg developers
built on May 27 2014 16:46:03 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu9)
configuration:
libavutil 51. 73.101 / 51. 73.101
libavcodec 54. 59.100 / 54. 59.100
libavformat 54. 29.104 / 54. 29.104
libavdevice 54. 2.101 / 54. 2.101
libavfilter 3. 17.100 / 3. 17.100
libswscale 2. 1.101 / 2. 1.101
libswresample 0. 15.100 / 0. 15.100
Truncating packet of size 250000 to 102381
[mxf @ 0x208f3e0] Estimating duration from bitrate, this may be inaccurate
Input #0, mxf, from 'Sample.mxf':
Metadata:
timecode : 10:00:00:01
Duration: 00:00:00.16, start: 0.000000, bitrate: 52428 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 152:135 DAR 4:3], 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s24le, 48000 Hz, 8 channels, s32, 9216 kb/s
Attachments (4)
Change History (15)
by , 11 years ago
| Attachment: | Sample.mxf added |
|---|
by , 11 years ago
Full console output of git HEAD with -v 9 -loglevel 99
follow-up: 2 comment:1 by , 11 years ago
| Component: | ffmpeg → avcodec |
|---|
Replying to Malizor:
Duration: 00:00:00.16, start: 0.000000, bitrate: 52428 kb/s
Do you believe that this value is correct?
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 152:135 DAR 4:3], 50000 kb/s
Showing a bitrate for a mpegvideo stream was assumed to be wrong (there is no bitrate written in the stream), this is why max. 50000 kb/s is shown now. Do you have any indication that the change was wrong?
follow-up: 3 comment:2 by , 11 years ago
Replying to cehoyos:
Replying to Malizor:
Duration: 00:00:00.16, start: 0.000000, bitrate: 52428 kb/sDo you believe that this value is correct?
Yes.
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 152:135 DAR 4:3], 50000 kb/sShowing a bitrate for a mpegvideo stream was assumed to be wrong (there is no bitrate written in the stream), this is why
max. 50000 kb/sis shown now. Do you have any indication that the change was wrong?
The full video file is 40G and is 1h 26mn long. New versions of ffmpeg detect it as being 9h 48m long with the very low bitrate that can still be seen with the attached sample.
I understand what you say about the bitrate, but it's sure that it is truly higher than the detected 9118 kb/s.
Also, as an additional test, I noticed that mediainfo also return the right metadata.
follow-up: 4 comment:3 by , 11 years ago
Replying to Malizor:
Replying to cehoyos:
Replying to Malizor:
Duration: 00:00:00.16, start: 0.000000, bitrate: 52428 kb/sDo you believe that this value is correct?
Yes.
The full video file is 40G and is 1h 26mn long.
Does this really imply ~50Mb/s? Doesn't sound correct to me.
How does old ffmpeg -i look for your complete 40G sample?
New versions of ffmpeg detect it as being 9h 48m long
And a warning is shown that this value is maybe incorrect.
I understand what you say about the bitrate, but it's sure that it is truly higher than the detected 9118 kb/s.
Of course.
The bitrate of the file is unknown / wrong because the video stream doesn't store a bitrate.
follow-up: 5 comment:4 by , 11 years ago
Replying to cehoyos:
Replying to Malizor:
The full video file is 40G and is 1h 26mn long.
Sorry, in fact it is truly 1:48:31 long (as verified by playing the video in VLC 2.0.8)
Does this really imply ~50Mb/s? Doesn't sound correct to me.
How does oldffmpeg -ilook for your complete 40G sample?
0.10.10 (good estimation):
ffmpeg -i ~/file_1_VR_16_PCBD_1.mxf
ffmpeg version 0.10.10 Copyright (c) 2000-2013 the FFmpeg developers
built on May 28 2014 11:23:04 with gcc 4.8.1
configuration:
libavutil 51. 35.100 / 51. 35.100
libavcodec 53. 61.100 / 53. 61.100
libavformat 53. 32.100 / 53. 32.100
libavdevice 53. 4.100 / 53. 4.100
libavfilter 2. 61.100 / 2. 61.100
libswscale 2. 1.100 / 2. 1.100
libswresample 0. 6.100 / 0. 6.100
[mxf @ 0x29843a0] Estimating duration from bitrate, this may be inaccurate
Input #0, mxf, from '/home/malizor/file_1_VR_16_PCBD_1.mxf':
Duration: 01:48:31.68, start: 0.000000, bitrate: 49999 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 152:135 DAR 4:3], 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s24le, 48000 Hz, 8 channels, s32, 9216 kb/s
At least one output file must be specified
1.0 (estimation a bit too short):
ffmpeg -i ~/file_1_VR_16_PCBD_1.mxf
ffmpeg version 1.0 Copyright (c) 2000-2012 the FFmpeg developers
built on May 27 2014 17:07:38 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu9)
configuration:
libavutil 51. 73.101 / 51. 73.101
libavcodec 54. 59.100 / 54. 59.100
libavformat 54. 29.104 / 54. 29.104
libavdevice 54. 2.101 / 54. 2.101
libavfilter 3. 17.100 / 3. 17.100
libswscale 2. 1.101 / 2. 1.101
libswresample 0. 15.100 / 0. 15.100
[mxf @ 0x1d50240] Estimating duration from bitrate, this may be inaccurate
Guessed Channel Layout for Input Stream #0.1 : 7.1
Input #0, mxf, from '/home/malizor/file_1_VR_16_PCBD_1.mxf':
Metadata:
timecode : 10:00:00:01
Duration: 01:31:38.24, start: 0.000000, bitrate: 59215 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x608 [SAR 152:135 DAR 4:3], 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s24le, 48000 Hz, 7.1, s32, 9216 kb/s
At least one output file must be specified
HEAD (estimation way too big):
ffmpeg -i ~/file_1_VR_16_PCBD_1.mxf
ffmpeg version N-63469-g5863207 Copyright (c) 2000-2014 the FFmpeg developers
built on May 27 2014 16:20:47 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu9)
configuration:
libavutil 52. 87.100 / 52. 87.100
libavcodec 55. 65.100 / 55. 65.100
libavformat 55. 41.100 / 55. 41.100
libavdevice 55. 13.101 / 55. 13.101
libavfilter 4. 5.100 / 4. 5.100
libswscale 2. 6.100 / 2. 6.100
libswresample 0. 19.100 / 0. 19.100
[mxf @ 0x3156ae0] Estimating duration from bitrate, this may be inaccurate
Guessed Channel Layout for Input Stream #0.1 : 7.1
Input #0, mxf, from '/home/malizor/file_1_VR_16_PCBD_1.mxf':
Metadata:
application_platform: Omneon Media Api (mqx)
uid : 98a72bb5-4bba-e111-92d9-00d0280f7410
generation_uid : aca72bb5-4bba-e111-bc13-00d0280f7410
company_name : Omneon Inc.
product_name : Omneon Media Subsystem
modification_date: 2012-06-19 20:16:52
product_version : 6.3.1.0.release
product_uid : 00000000-0000-0010-8000-050e0b010602
timecode : 10:00:00:01
Duration: 09:48:48.04, start: 0.000000, bitrate: 9215 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv), 720x608 [SAR 152:135 DAR 4:3], max. 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s24le, 48000 Hz, 7.1, s32, 9216 kb/s
At least one output file must be specified
New versions of ffmpeg detect it as being 9h 48m long
And a warning is shown that this value is maybe incorrect.
Indeed.
So the problem is that the estimation was better in older versions.
I understand what you say about the bitrate, but it's sure that it is truly higher than the detected 9118 kb/s.
Of course.
The bitrate of the file is unknown / wrong because the video stream doesn't store a bitrate.
Apparently somthing changed in the way ffmpeg try to guess the bitrate, and it has regressed for some videos like this one.
follow-up: 6 comment:5 by , 11 years ago
Replying to Malizor:
Replying to cehoyos:
Replying to Malizor:
The full video file is 40G and is 1h 26mn long.
Sorry, in fact it is truly 1:48:31 long (as verified by playing the video in VLC 2.0.8)
Could you add the exact file size?
ffmpeg -i input -f null - tells you the exact length.
I understand what you say about the bitrate, but it's sure that it is truly higher than the detected 9118 kb/s.
Of course.
The bitrate of the file is unknown / wrong because the video stream doesn't store a bitrate.
Apparently somthing changed in the way ffmpeg try to guess the bitrate, and it has regressed for some videos like this one.
No. (Or at least I find this wording misleading.)
The value written in mpegvideo streams is not the actual bitrate but the maximum bitrate.
For your (mxf) file, the values are nearly identical, for (more typical) dvb streams, the value is completely wrong. It was therefore decided not to use the (possibly wrong) maximum bitrate value as actual video bitrate.
comment:6 by , 11 years ago
Replying to cehoyos:
Replying to Malizor:
Replying to cehoyos:
Replying to Malizor:
The full video file is 40G and is 1h 26mn long.
Sorry, in fact it is truly 1:48:31 long (as verified by playing the video in VLC 2.0.8)
Could you add the exact file size?
ffmpeg -i input -f null -tells you the exact length.
I get this: frame=130095 fps=221 q=0.0 Lsize=N/A time=01:26:43.80 bitrate=N/A
Why is it not the same as what I get by playing the file in VLC? (I can seek to the very end of the video... Could it be framerate related?)
comment:8 by , 11 years ago
comment:9 by , 11 years ago
| Keywords: | mpegvideo regression added |
|---|
I am not sure if this can be fixed.
comment:10 by , 11 years ago
| Keywords: | mpeg2video added; mpegvideo removed |
|---|
comment:11 by , 10 years ago
| Reproduced by developer: | set |
|---|---|
| Resolution: | → fixed |
| Status: | new → closed |
Sample file to reproduce the problem