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

Paul B Mahol onemda at gmail.com
Fri Jun 1 12:53:50 EEST 2018

On 6/1/18, Jerome Martinez <jerome at mediaarea.net> wrote:
> On 08/02/2018 11:28, Jerome Martinez wrote:
>> Currently RGB and RGBA 12-bit are supported by DPX decoder only if
>> component values are padded (packing "Filled to 32-bit words, method A").
>> This patch adds decoding of RGB and RGBA 12-bit with no padding
>> (packing "Packed into 32-bit words").
>> As I have no file with line boundaries not aligned on 32-bit, I can
>> not have good tests about the stride computing (so code about non
>> aligned boundaries is theory) so I preferred to limit risks by
>> decoding only if line boundaries are aligned on 32-bit words:
>> - 8 pixels for RGB (8 pixels x 3 components x 12 bits = 288 bits = 9 x
>> 32-bit words)
>> - 2 pixels for RGBA (2 pixels x 4 components x 12 bits = 3 x 32-bit
>> words)
>> I think Little Endian parsing is fine thanks to the generic code about
>> Big vs Little endian but I have no Little Endian test file so I also
>> limited the decoding to Big Endian files.
>> Would be happy to check with cases I was not able to check if someone
>> provides files.
> Since the email, RGB 12-bit packed decoding was pushed.
> Attached is the patch for RGBA 12-bit packed decoding, rebased.
> Test file:
> https://trac.ffmpeg.org/attachment/ticket/5639/12bit_a.dpx


More information about the ffmpeg-devel mailing list