avcodec/mpegvideo: Fix null pointer dereference with grayscale decoding with mpeg2_field_encoding.ts

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2015-05-09 16:20:12 +02:00
parent 33529104e5
commit cf31e2df08

View File

@ -1896,11 +1896,13 @@ int ff_mpv_frame_start(MpegEncContext *s, AVCodecContext *avctx)
for(i=0; i<avctx->height; i++)
memset(s->last_picture_ptr->f->data[0] + s->last_picture_ptr->f->linesize[0]*i,
0x80, avctx->width);
for(i=0; i<FF_CEIL_RSHIFT(avctx->height, v_chroma_shift); i++) {
memset(s->last_picture_ptr->f->data[1] + s->last_picture_ptr->f->linesize[1]*i,
0x80, FF_CEIL_RSHIFT(avctx->width, h_chroma_shift));
memset(s->last_picture_ptr->f->data[2] + s->last_picture_ptr->f->linesize[2]*i,
0x80, FF_CEIL_RSHIFT(avctx->width, h_chroma_shift));
if (s->last_picture_ptr->f->data[2]) {
for(i=0; i<FF_CEIL_RSHIFT(avctx->height, v_chroma_shift); i++) {
memset(s->last_picture_ptr->f->data[1] + s->last_picture_ptr->f->linesize[1]*i,
0x80, FF_CEIL_RSHIFT(avctx->width, h_chroma_shift));
memset(s->last_picture_ptr->f->data[2] + s->last_picture_ptr->f->linesize[2]*i,
0x80, FF_CEIL_RSHIFT(avctx->width, h_chroma_shift));
}
}
if(s->codec_id == AV_CODEC_ID_FLV1 || s->codec_id == AV_CODEC_ID_H263){