More detailed explenation when convert context could not be created
More detailed explenation when convert context could not be created

Summary: There was not enough explenation when context was not
created. Now we provide information whith pixel format conversion
was requested.

mrduongnv/AndroidFFmpeg,mondoktamas/AndroidFFmpeg,guoyuqing/ffmpeg,hank5000/VPlayer_lib,boke/AndroidFFmpeg,code-guru/AndroidFFmpeg-appunite,xinran505982/AndroidVideoPlayer-master,appunite/AndroidFFmpeg,shakin/AndroidFFmpeg,mobdim/AndroidFFmpeg,xinran505982/AndroidVideoPlayer-master,kyawkyaw/AndroidFFmpeg,QDPeng/AndroidFFmpeg,mondoktamas/AndroidFFmpeg,ShawnKoo/AndroidFFmpeg,mobdim/AndroidFFmpeg,shakin/AndroidFFmpeg,shakin/AndroidFFmpeg,mrduongnv/AndroidFFmpeg,q273255702/AndroidFFmpeg,lulufei/AndroidFFmpeg,appunite/AndroidFFmpeg,guoyuqing/ffmpeg,MisterRager/AndroidFFmpeg,zzhhui/AndroidFFmpeg,q273255702/AndroidFFmpeg,hank5000/VPlayer_lib,mondoktamas/AndroidFFmpeg,lulufei/AndroidFFmpeg,code-guru/AndroidFFmpeg-appunite,shine-chen/AndroidFFmpeg-with-RTMP,zzhhui/AndroidFFmpeg,kyawkyaw/AndroidFFmpeg,lulufei/AndroidFFmpeg,guoyuqing/ffmpeg,hank5000/VPlayer_lib,q273255702/AndroidFFmpeg,mobdim/AndroidFFmpeg,sitexa/AndroidFFmpeg,10045125/AndroidFFmpeg,zzhhui/AndroidFFmpeg,shakin/AndroidFFmpeg,sitexa/AndroidFFmpeg,mrduongnv/AndroidFFmpeg,10045125/AndroidFFmpeg,QDPeng/AndroidFFmpeg,kyawkyaw/AndroidFFmpeg,ShawnKoo/AndroidFFmpeg,shine-chen/AndroidFFmpeg-with-RTMP,code-guru/AndroidFFmpeg-appunite,ShawnKoo/AndroidFFmpeg,QDPeng/AndroidFFmpeg,kyawkyaw/AndroidFFmpeg,xinran505982/AndroidVideoPlayer-master,sitexa/AndroidFFmpeg,hank5000/VPlayer_lib,shine-chen/AndroidFFmpeg-with-RTMP,matthewn4444/VPlayer_lib,MisterRager/AndroidFFmpeg,MisterRager/AndroidFFmpeg,matthewn4444/VPlayer_lib,boke/AndroidFFmpeg,10045125/AndroidFFmpeg,q273255702/AndroidFFmpeg,mobdim/AndroidFFmpeg,QDPeng/AndroidFFmpeg,MisterRager/AndroidFFmpeg,zzhhui/AndroidFFmpeg,matthewn4444/VPlayer_lib,ShawnKoo/AndroidFFmpeg,boke/AndroidFFmpeg,appunite/AndroidFFmpeg,mrduongnv/AndroidFFmpeg,sitexa/AndroidFFmpeg,mondoktamas/AndroidFFmpeg,lulufei/AndroidFFmpeg,appunite/AndroidFFmpeg,code-guru/AndroidFFmpeg-appunite,shine-chen/AndroidFFmpeg-with-RTMP,guoyuqing/ffmpeg,boke/AndroidFFmpeg,10045125/AndroidFFmpeg,matthewn4444/VPlayer_lib,xinran505982/AndroidVideoPlayer-master