diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c index 856947b656..2528b795fe 100644 --- a/libavcodec/mjpegdec.c +++ b/libavcodec/mjpegdec.c @@ -1044,6 +1044,20 @@ static av_always_inline void mjpeg_copy_block(MJpegDecodeContext *s, } } +static void shift_output(MJpegDecodeContext *s, uint8_t *ptr, int linesize) +{ + int block_x, block_y; + if (s->bits > 8) { + for (block_y=0; block_y<8; block_y++) + for (block_x=0; block_x<8; block_x++) + *(uint16_t*)(ptr + 2*block_x + block_y*linesize) <<= 16 - s->bits; + } else { + for (block_y=0; block_y<8; block_y++) + for (block_x=0; block_x<8; block_x++) + *(ptr + block_x + block_y*linesize) <<= 8 - s->bits; + } +} + static int mjpeg_decode_scan(MJpegDecodeContext *s, int nb_components, int Ah, int Al, const uint8_t *mb_bitmask, const AVFrame *reference) @@ -1123,18 +1137,8 @@ static int mjpeg_decode_scan(MJpegDecodeContext *s, int nb_components, int Ah, return AVERROR_INVALIDDATA; } s->dsp.idct_put(ptr, linesize[c], s->block); - if (s->bits & 7) { - int block_x, block_y; - if (s->bits > 8) { - for (block_y=0; block_y<8; block_y++) - for (block_x=0; block_x<8; block_x++) - *(uint16_t*)(ptr + 2*block_x + block_y*linesize[c]) <<= 16 - s->bits; - } else { - for (block_y=0; block_y<8; block_y++) - for (block_x=0; block_x<8; block_x++) - *(ptr + 2*block_x + block_y*linesize[c]) <<= 8 - s->bits; - } - } + if (s->bits & 7) + shift_output(s, ptr, linesize[c]); } } else { int block_idx = s->block_stride[c] * (v * mb_y + y) +