[FFmpeg-devel] support pad/crop for exspect yuv planar pixel formats

[rachel li]

I attempt to use -pad -crop parameter,convert a avi file to gif file ,I Know that ffmpeg cannot support yuv planar pixel formats patch logs an errorin av_picture_crop()/av_picture_pad() 

I modify the code : enc->pix_fmt=PIX_FMT_YUV420P before the function do_video_out run pad/crop, and before encode change enc->pix_fmt to origal pixel foramts,

now the convert finshed ,but I rellealy want to know ,withe the modity ,has any question I cannot think out.

 or how to solute the question,pad/crop 

but I donnot know how to transfer the function "is_yuv_planar "in file ffmpeg.c