[FFmpeg-devel] APNG encoder can work incorrectly

[Dmitriy]

In come cases APNG encoder generate only static video.

The errors are located in the apng_encode_frame function (pngenc.c file).

The
av_frame_copy(diffFrame, s->last_frame);
and
av_frame_copy(diffFrame, s->last_frame);

functions doesn't work if the image size was changed in
apng_do_inverse_blend function and return error code.

you need insert the following codes

diffFrame->width = pict->width;
diffFrame->height = pict->height;
av_frame_copy(diffFrame, s->last_frame);

and

diffFrame->width = pict->width;
diffFrame->height = pict->height;
av_frame_copy(diffFrame, s->last_frame);

to restore image size before recovery diffFrame image.

-- 
С уважением,
 Dmitriy                          mailto:DiZNet at mail.ru