Seek to 0 jpeg image input file image causes eof of the input stream

[remigiusz.zukowski]

When input file is an jpeg image (any valid jpeg image) and I seek the file to 0 then the demuxer gives empty stream by immediately outputting eof.
or
I cannot rewind jpeg input stream to the beginning by seeking to 0 or any other value since the demuxer signals eof after any seek.

Does not happen for png image files.
Does not happen with 20151020-git-e91cd8a, cannot determine when exactly it was introduced.

How to reproduce

ffmpeg -ss 0 -i input.jpg output.jpg

ffmpeg version 20170130-cba4f0e

Console output

ffmpeg -v 9 -loglevel 99 -ss -1 -i d:\1.jpg d:\file.jpg

ffmpeg version N-83280-gcba4f0e Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 5.4.0 (GCC)
  configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --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-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib
  libavutil      55. 45.100 / 55. 45.100
  libavcodec     57. 75.100 / 57. 75.100
  libavformat    57. 65.100 / 57. 65.100
  libavdevice    57.  2.100 / 57.  2.100
  libavfilter     6. 71.100 /  6. 71.100
  libswscale      4.  3.101 /  4.  3.101
  libswresample   2.  4.100 /  2.  4.100
  libpostproc    54.  2.100 / 54.  2.100
Splitting the commandline.
Reading option '-v' ... matched as option 'v' (set logging level) with argument '9'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument '99'.
Reading option '-ss' ... matched as option 'ss' (set the start time offset) with argument '0'.
Reading option '-i' ... matched as input url with argument 'd:\1.jpg'.
Reading option 'd:\file.jpg' ... matched as output url.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option v (set logging level) with argument 9.
Successfully parsed a group of options.
Parsing a group of options: input url d:\1.jpg.
Applying option ss (set the start time offset) with argument 0.
Successfully parsed a group of options.
Opening an input file: d:\1.jpg.
[file @ 00000000004fae00] Setting default whitelist 'file,crypto'
Probing image2 score:50 size:2048
Probing jpeg_pipe score:25 size:2048
[image2 @ 00000000004fa400] Format image2 probed with size=2048 and score=50
[image2 @ 00000000004fa400] Before avformat_find_stream_info() pos: 0 bytes read:32768 seeks:0 nb_streams:1
[mjpeg @ 000000000050c4c0] marker=d8 avail_size_in_buf=266292
[mjpeg @ 000000000050c4c0] marker parser used 0 bytes (0 bits)
[mjpeg @ 000000000050c4c0] marker=e0 avail_size_in_buf=266290
[mjpeg @ 000000000050c4c0] marker parser used 16 bytes (128 bits)
[mjpeg @ 000000000050c4c0] marker=e1 avail_size_in_buf=266272
[mjpeg @ 000000000050c4c0] marker parser used 77 bytes (616 bits)
[mjpeg @ 000000000050c4c0] marker=db avail_size_in_buf=266192
[mjpeg @ 000000000050c4c0] index=0
[mjpeg @ 000000000050c4c0] qscale[0]: 2
[mjpeg @ 000000000050c4c0] marker parser used 67 bytes (536 bits)
[mjpeg @ 000000000050c4c0] marker=db avail_size_in_buf=266123
[mjpeg @ 000000000050c4c0] index=1
[mjpeg @ 000000000050c4c0] qscale[1]: 5
[mjpeg @ 000000000050c4c0] marker parser used 67 bytes (536 bits)
[mjpeg @ 000000000050c4c0] marker=c0 avail_size_in_buf=266054
[mjpeg @ 000000000050c4c0] Changing bps from 0 to 8
[mjpeg @ 000000000050c4c0] sof0: picture: 1600x1200
[mjpeg @ 000000000050c4c0] component 0 2:2 id: 0 quant:0
[mjpeg @ 000000000050c4c0] component 1 1:1 id: 1 quant:1
[mjpeg @ 000000000050c4c0] component 2 1:1 id: 2 quant:1
[mjpeg @ 000000000050c4c0] pix fmt id 22111100
[mjpeg @ 000000000050c4c0] marker parser used 17 bytes (136 bits)
[mjpeg @ 000000000050c4c0] marker=c4 avail_size_in_buf=266035
[mjpeg @ 000000000050c4c0] marker parser used 0 bytes (0 bits)
[mjpeg @ 000000000050c4c0] marker=c4 avail_size_in_buf=266002
[mjpeg @ 000000000050c4c0] marker parser used 0 bytes (0 bits)
[mjpeg @ 000000000050c4c0] marker=c4 avail_size_in_buf=265819
[mjpeg @ 000000000050c4c0] marker parser used 0 bytes (0 bits)
[mjpeg @ 000000000050c4c0] marker=c4 avail_size_in_buf=265786
[mjpeg @ 000000000050c4c0] marker parser used 0 bytes (0 bits)
[mjpeg @ 000000000050c4c0] escaping removed 561 bytes
[mjpeg @ 000000000050c4c0] marker=da avail_size_in_buf=265603
[mjpeg @ 000000000050c4c0] marker parser used 265042 bytes (2120336 bits)
[mjpeg @ 000000000050c4c0] marker=d9 avail_size_in_buf=0
[mjpeg @ 000000000050c4c0] decode frame unused 0 bytes
[image2 @ 00000000004fa400] stream 0: start_time: 0.000 duration: 0.040
[image2 @ 00000000004fa400] format: start_time: 0.000 duration: 0.040 bitrate=53258 kb/s
[image2 @ 00000000004fa400] After avformat_find_stream_info() pos: 266294 bytes read:266294 seeks:0 frames:1
Input #0, image2, from 'd:\1.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: 53258 kb/s
    Stream #0:0, 1, 1/25: Video: mjpeg, 1 reference frame, yuvj420p(pc, bt470bg/unknown/unknown, center), 1600x1200 [SAR 1:1 DAR 4:3], 0/1, 25 tbr, 25 tbn, 25 tbc
Successfully opened the file.
Parsing a group of options: output url d:\file.jpg.
Successfully parsed a group of options.
Opening an output file: d:\file.jpg.
Successfully opened the file.
Initializing cuvid transcoding
detected 4 logical cores
[graph 0 input from stream 0:0 @ 000000000050b680] Setting 'video_size' to value '1600x1200'
[graph 0 input from stream 0:0 @ 000000000050b680] Setting 'pix_fmt' to value '12'
[graph 0 input from stream 0:0 @ 000000000050b680] Setting 'time_base' to value '1/25'
[graph 0 input from stream 0:0 @ 000000000050b680] Setting 'pixel_aspect' to value '1/1'
[graph 0 input from stream 0:0 @ 000000000050b680] Setting 'sws_param' to value 'flags=2'
[graph 0 input from stream 0:0 @ 000000000050b680] Setting 'frame_rate' to value '25/1'
[graph 0 input from stream 0:0 @ 000000000050b680] w:1600 h:1200 pixfmt:yuvj420p tb:1/25 fr:25/1 sar:1/1 sws_param:flags=2
[format @ 0000000000513ba0] compat: called with args=[yuvj420p|yuvj422p|yuvj444p]
[format @ 0000000000513ba0] Setting 'pix_fmts' to value 'yuvj420p|yuvj422p|yuvj444p'
[AVFilterGraph @ 00000000006675a0] query_formats: 5 queried, 4 merged, 0 already done, 0 delayed
[mjpeg @ 0000000000507a40] Forcing thread count to 1 for MJPEG encoding, use -thread_type slice or a constant quantizer if you want to use multiple cpu cores
[mjpeg @ 0000000000507a40] intra_quant_bias = 96 inter_quant_bias = 0
Output #0, image2, to 'd:\file.jpg':
  Metadata:
    encoder         : Lavf57.65.100
    Stream #0:0, 0, 1/25: Video: mjpeg, 1 reference frame, yuvj420p(pc, center), 1600x1200 [SAR 1:1 DAR 4:3], 0/1, q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc
    Metadata:
      encoder         : Lavc57.75.100 mjpeg
    Side data:
      cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> mjpeg (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
    Last message repeated 1 times
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 speed=   0x    
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Input file #0 (d:\1.jpg):
  Input stream #0:0 (video): 0 packets read (0 bytes); 0 frames decoded; 
  Total: 0 packets (0 bytes) demuxed
Output file #0 (d:\file.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 @ 0000000000668d00] Statistics: 266294 bytes read, 0 seeks

[Carl Eugen Hoyos]

Please either explain how I can reproduce the issue (sample code) or run git bisect to find the change introducing the issue.

[Carl Eugen Hoyos]

For -ss 0, this is a regression since e70d56b8 related to ticket #4849, I don't know what -ss -1 is supposed to do / has never worked afaict.

[Martin Pecka]

This has still been a problem nowadays. With ffmpeg 7.0.2, I still get empty output when seeking a JPG image to 0 (while I get 1 frame with no seek). FFMpeg reports a duration of 1/25 s and 1 frame, so I'd expect that seeking to 0 should work.

$ ffmpeg -ss 0 -i img.jpg img2.jpg
ffmpeg version 7.0.2-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 8 (Debian 8.3.0-6)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-libgme --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
  libavutil      59.  8.100 / 59.  8.100
  libavcodec     61.  3.100 / 61.  3.100
  libavformat    61.  1.100 / 61.  1.100
  libavdevice    61.  1.100 / 61.  1.100
  libavfilter    10.  1.100 / 10.  1.100
  libswscale      8.  1.100 /  8.  1.100
  libswresample   5.  1.100 /  5.  1.100
  libpostproc    58.  1.100 / 58.  1.100
Input #0, image2, from 'img.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: 1059428 kb/s
  Stream #0:0: Video: mjpeg (Baseline), yuvj444p(pc, bt470bg/unknown/unknown), 3024x4032 [SAR 72:72 DAR 3:4], 25 fps, 25 tbr, 25 tbn
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> mjpeg (native))
Press [q] to stop, [?] for help
[vost#0:0/mjpeg @ 0x3785b740] No filtered frames for output stream, trying to initialize anyway.
Output #0, image2, to 'img2.jpg':
  Metadata:
    encoder         : Lavf61.1.100
  Stream #0:0: Video: mjpeg, yuvj444p(pc, progressive), 3024x4032 [SAR 72:72 DAR 3:4], q=2-31, 200 kb/s, 25 fps, 25 tbn
      Metadata:
        encoder         : Lavc61.3.100 mjpeg
      Side data:
        cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: N/A
[out#0/image2 @ 0x37857d00] video:0KiB audio:0KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown
[out#0/image2 @ 0x37857d00] Output file is empty, nothing was encoded(check -ss / -t / -frames parameters if used)
frame=    0 fps=0.0 q=0.0 Lsize=N/A time=N/A bitrate=N/A speed=N/A