Opened 5 years ago

Closed 3 years ago

#4358 closed defect (invalid)

ffprobe shows different results for regular file and stdin

Reported by: wifyer Owned by:
Priority: normal Component: undetermined
Version: unspecified Keywords:
Cc: nfxjfg@googlemail.com Blocked By:
Blocking: Reproduced by developer: no
Analyzed by developer: no

Description

Summary of the bug: The same file passed to ffprobe directly and via pipe:0 produces different results (duration not shown)
How to reproduce:

1) Reading file from pipe. Duration is not shown.
cat out.mp3 | ffprobe -i pipe:0 -print_format json -show_format -show_streams
ffprobe version N-70348-g9564375 Copyright (c) 2007-2015 the FFmpeg developers
  built with gcc 4.9.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnu
tls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-
libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-l
ibrtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --
enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --ena
ble-libxvid --enable-lzma --enable-decklink --enable-zlib
  libavutil      54. 19.100 / 54. 19.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 23.106 / 56. 23.106
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
{
Input #0, mp3, from 'pipe:0':
  Metadata:
    encoder         : Lavf56.23.106
  Duration: N/A, start: 0.025057, bitrate: 128 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 128 kb/s
    Metadata:
      encoder         : Lavc56.26
    "streams": [
        {
            "index": 0,
            "codec_name": "mp3",
            "codec_long_name": "MP3 (MPEG audio layer 3)",
            "codec_type": "audio",
            "codec_time_base": "1/44100",
            "codec_tag_string": "[0][0][0][0]",
            "codec_tag": "0x0000",
            "sample_fmt": "s16p",
            "sample_rate": "44100",
            "channels": 2,
            "channel_layout": "stereo",
            "bits_per_sample": 0,
            "r_frame_rate": "0/0",
            "avg_frame_rate": "0/0",
            "time_base": "1/14112000",
            "start_pts": 353600,
            "start_time": "0.025057",
            "bit_rate": "128000",
            "disposition": {
                "default": 0,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0
            },
            "tags": {
                "encoder": "Lavc56.26"
            }
        }
    ],
    "format": {
        "filename": "pipe:0",
        "nb_streams": 1,
        "nb_programs": 0,
        "format_name": "mp3",
        "format_long_name": "MP2/3 (MPEG audio layer 2/3)",
        "start_time": "0.025057",
        "bit_rate": "128000",
        "probe_score": 51,
        "tags": {
            "encoder": "Lavf56.23.106"
        }
    }
}
2) The same file passed directly. Duration is shown.
ffprobe -i out.mp3 -print_format json -show_format -show_streams
ffprobe version N-70348-g9564375 Copyright (c) 2007-2015 the FFmpeg developers
  built with gcc 4.9.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnu
tls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-
libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-l
ibrtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --
enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --ena
ble-libxvid --enable-lzma --enable-decklink --enable-zlib
  libavutil      54. 19.100 / 54. 19.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 23.106 / 56. 23.106
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
{
Input #0, mp3, from 'out.mp3':
  Metadata:
    encoder         : Lavf56.23.106
  Duration: 00:03:28.12, start: 0.025057, bitrate: 128 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 128 kb/s
    Metadata:
      encoder         : Lavc56.26
    "streams": [
        {
            "index": 0,
            "codec_name": "mp3",
            "codec_long_name": "MP3 (MPEG audio layer 3)",
            "codec_type": "audio",
            "codec_time_base": "1/44100",
            "codec_tag_string": "[0][0][0][0]",
            "codec_tag": "0x0000",
            "sample_fmt": "s16p",
            "sample_rate": "44100",
            "channels": 2,
            "channel_layout": "stereo",
            "bits_per_sample": 0,
            "r_frame_rate": "0/0",
            "avg_frame_rate": "0/0",
            "time_base": "1/14112000",
            "start_pts": 353600,
            "start_time": "0.025057",
            "duration_ts": 2936954880,
            "duration": "208.117551",
            "bit_rate": "128000",
            "disposition": {
                "default": 0,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0
            },
            "tags": {
                "encoder": "Lavc56.26"
            }
        }
    ],
    "format": {
        "filename": "out.mp3",
        "nb_streams": 1,
        "nb_programs": 0,
        "format_name": "mp3",
        "format_long_name": "MP2/3 (MPEG audio layer 2/3)",
        "start_time": "0.025057",
        "duration": "208.117551",
        "size": "3330133",
        "bit_rate": "128009",
        "probe_score": 51,
        "tags": {
            "encoder": "Lavf56.23.106"
        }
    }
}

Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.

Change History (5)

comment:1 Changed 5 years ago by wifyer

  • Component changed from undetermined to ffprobe

comment:2 Changed 5 years ago by gjdfgh

  • Cc nfxjfg@googlemail.com added
  • Component changed from ffprobe to undetermined

For most files it can't know how long the mp3's duration is if the file length is unknown. The file length is obviously not known with a pipe.

comment:3 Changed 5 years ago by wifyer

Ok. I just want to understand. Stream length could be calculated while stream is read. In this case stream is consumed totally so it's not so difficult to get its length.

comment:4 Changed 5 years ago by gjdfgh

I agree that updating the stream duration while reading it would be nice.

There's just nobody who would be willing to fight this mess and write a patch.

comment:5 Changed 3 years ago by cehoyos

  • Resolution set to invalid
  • Status changed from new to closed
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