[FFmpeg-devel] [PATCH] avcodec/dpx: Support for RGB 12-bit packed decoding

Paul B Mahol onemda at gmail.com
Tue Apr 10 17:16:37 EEST 2018


On 4/10/18, Kieran O Leary <kieran.o.leary at gmail.com> wrote:
> Actually, here's another test that might be a bit more meaningful.
> This is using graphicksmagic and the identify/signature command in
> order to generate sha256 hashes for the image data only.
>
> It is producing identical hashes for:
> 1. The original 12-bit DPX from Da Vinci Resolve (not packed to 16-bit)
> 2. The graphicsmagick 12-bit DPX to 12-bit DPX (padded to 16-bit DPX) file
> 3. The ffmpeg convert 12-bit DPX to 12-bit DPX (padded to 16-bit DPX)
> which uses the ffmpeg decoder with Jerome's patch.
>
> $ gm identify -verbose
> 6e0edc3b-7d89-4710-8b9a-66c8c990f9dc_1_00094787.dpx  |grep -i
> signature
>
>   Signature:
> 3fb67059dca860c483b1deac912973b76d48fa9f0114d63e8116cff69d55bb4c
>
> $ gm identify -verbose gm_dpx_to_dpx.dpx  |grep -i signature
>
>   Signature:
> 3fb67059dca860c483b1deac912973b76d48fa9f0114d63e8116cff69d55bb4c
>
>
> $ gm identify -verbose ffmpeg_dpx_to_dpx.dpx  |grep -i signature
>
>   Signature:
> 3fb67059dca860c483b1deac912973b76d48fa9f0114d63e8116cff69d55bb4c
>
> Hopefully this is a bit better than just using ffmpeg?

No, you must not use tragic software ever.

Besides ffmpeg also can give you checksums for image only.
See framehash muxer, and it can give you sha512 hash.


More information about the ffmpeg-devel mailing list