[FFmpeg-user] dpx image sequence to ffv1 mkv issues

[Kieran O Leary]

Hi,

On Mon, Nov 6, 2017 at 9:18 AM, Camara Caamaño, Xavier
<xcamara at gencat.cat> wrote:
> Dear list,
>
> I have some issues related to the wrapping of a dpx imatge sequence into ffv1 in mkv container.
>
> I get an error when I try to wrap a 6K 16bit image sequence: Invalid minimum required packet size
> I know I'm pushing a lot, but these are the original scanned images of a 35mm negative film we get in our film archive's scanner.
>
I did some synthetic testing using ffmpeg generated files using
lavfi/testsrc and was able to reproduce the issue, so it's not related
to your input file or DPX in general.

./ffmpeg -f lavfi -i testsrc=size=6192x4668 -vframes 1 -c:v ffv1
-level 3  -f null -

ffmpeg version N-88563-gd68a557 Copyright (c) 2000-2017 the FFmpeg developers

  built with Apple LLVM version 8.0.0 (clang-800.0.42.1)

  configuration:

  libavutil      56.  0.100 / 56.  0.100

  libavcodec     58.  1.100 / 58.  1.100

  libavformat    58.  1.100 / 58.  1.100

  libavdevice    58.  0.100 / 58.  0.100

  libavfilter     7.  0.101 /  7.  0.101

  libswscale      5.  0.101 /  5.  0.101

  libswresample   3.  0.101 /  3.  0.101

Input #0, lavfi, from 'testsrc=size=6192x4668':

  Duration: N/A, start: 0.000000, bitrate: N/A

    Stream #0:0: Video: rawvideo (RGB[24] / 0x18424752), rgb24,
6192x4668 [SAR 1:1 DAR 516:389], 25 tbr, 25 tbn, 25 tbc

Stream mapping:

  Stream #0:0 -> #0:0 (rawvideo (native) -> ffv1 (native))

Press [q] to stop, [?] for help

Output #0, null, to 'pipe:':

  Metadata:

    encoder         : Lavf58.1.100

    Stream #0:0: Video: ffv1, bgr0, 6192x4668 [SAR 1:1 DAR 516:389],
q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc

    Metadata:

      encoder         : Lavc58.1.100 ffv1

[ffv1 @ 0x7ff574001800] Cannot allocate worst case packet size, the
encoding could fail

frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A
speed=0.185x

video:160kB audio:0kB subtitle:0kB other streams:0kB global
headers:0kB muxing overhead: unknown




> This is my command output:
>
> ffmpeg -f image2 -framerate 24 -start_number 0000000 -i "
> C:\Temp\6K dpx 16bit\%06d.dpx"  -strict -2 -c:v ffv1 -level 3 -g 1 -slicecrc 1 -
> slices 16 C:\Temp\test.mkv
> ffmpeg version N-82095-g5867234 Copyright (c) 2000-2016 the FFmpeg developers
>   built with gcc 5.4.0 (GCC)


This version looks old, which probably explains why your more recent
OSX version shows a different error.
[...]

> I don't really understand what the error and warning mean, can anybody enlighten me?

Neither do I really, seems to be something to do with frame size, as I
started experimenting with reducing the input frame size and found the
error went away when I got to 3224*4500. Adding a pixel to either of
those numbers results in the error.

./ffmpeg -f lavfi -i testsrc=size=3224x4500 -vframes 1 -c:v ffv1
-level 3  -f null -

ffmpeg version N-88563-gd68a557 Copyright (c) 2000-2017 the FFmpeg developers

  built with Apple LLVM version 8.0.0 (clang-800.0.42.1)

  configuration:

  libavutil      56.  0.100 / 56.  0.100

  libavcodec     58.  1.100 / 58.  1.100

  libavformat    58.  1.100 / 58.  1.100

  libavdevice    58.  0.100 / 58.  0.100

  libavfilter     7.  0.101 /  7.  0.101

  libswscale      5.  0.101 /  5.  0.101

  libswresample   3.  0.101 /  3.  0.101

Input #0, lavfi, from 'testsrc=size=3224x4500':

  Duration: N/A, start: 0.000000, bitrate: N/A

    Stream #0:0: Video: rawvideo (RGB[24] / 0x18424752), rgb24,
3224x4500 [SAR 1:1 DAR 806:1125], 25 tbr, 25 tbn, 25 tbc

Stream mapping:

  Stream #0:0 -> #0:0 (rawvideo (native) -> ffv1 (native))

Press [q] to stop, [?] for help

Output #0, null, to 'pipe:':

  Metadata:

    encoder         : Lavf58.1.100

    Stream #0:0: Video: ffv1, bgr0, 3224x4500 [SAR 1:1 DAR 806:1125],
q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc

    Metadata:

      encoder         : Lavc58.1.100 ffv1

frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A
speed=0.288x

video:147kB audio:0kB subtitle:0kB other streams:0kB global
headers:0kB muxing overhead: unknown

> I uploaded a dpx file at:
> https://wetransfer.com/downloads/bdcf070cade355e680cb504e46c1e97820171106090602/e88690d48775c2cca865dee6c4e133f220171106090602/e9c08d

Dear god 6K 16-bit DPX is HUGE.

Best,

Kieran.