diff options
| -rw-r--r-- | libavcodec/mjpegdec.c | 84 | ||||
| -rw-r--r-- | libavcodec/mjpegdec.h | 3 |
2 files changed, 55 insertions, 32 deletions
diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c index a230fa9529..da83cdfe2e 100644 --- a/libavcodec/mjpegdec.c +++ b/libavcodec/mjpegdec.c @@ -1316,43 +1316,26 @@ found: return val; } -int ff_mjpeg_decode_frame(AVCodecContext *avctx, - void *data, int *data_size, - AVPacket *avpkt) +int ff_mjpeg_find_marker(MJpegDecodeContext *s, + const uint8_t **buf_ptr, const uint8_t *buf_end, + const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size) { - const uint8_t *buf = avpkt->data; - int buf_size = avpkt->size; - MJpegDecodeContext *s = avctx->priv_data; - const uint8_t *buf_end, *buf_ptr; int start_code; - AVFrame *picture = data; - - s->got_picture = 0; // picture from previous image can not be reused - buf_ptr = buf; - buf_end = buf + buf_size; - while (buf_ptr < buf_end) { - /* find start next marker */ - start_code = find_marker(&buf_ptr, buf_end); - { - /* EOF */ - if (start_code < 0) { - goto the_end; - } else { - av_log(avctx, AV_LOG_DEBUG, "marker=%x avail_size_in_buf=%td\n", start_code, buf_end - buf_ptr); + start_code = find_marker(buf_ptr, buf_end); - if ((buf_end - buf_ptr) > s->buffer_size) + if ((buf_end - *buf_ptr) > s->buffer_size) { av_free(s->buffer); - s->buffer_size = buf_end-buf_ptr; + s->buffer_size = buf_end - *buf_ptr; s->buffer = av_malloc(s->buffer_size + FF_INPUT_BUFFER_PADDING_SIZE); - av_log(avctx, AV_LOG_DEBUG, "buffer too small, expanding to %d bytes\n", + av_log(s->avctx, AV_LOG_DEBUG, "buffer too small, expanding to %d bytes\n", s->buffer_size); } /* unescape buffer of SOS, use special treatment for JPEG-LS */ if (start_code == SOS && !s->ls) { - const uint8_t *src = buf_ptr; + const uint8_t *src = *buf_ptr; uint8_t *dst = s->buffer; while (src<buf_end) @@ -1360,7 +1343,7 @@ int ff_mjpeg_decode_frame(AVCodecContext *avctx, uint8_t x = *(src++); *(dst++) = x; - if (avctx->codec_id != CODEC_ID_THP) + if (s->avctx->codec_id != CODEC_ID_THP) { if (x == 0xff) { while (src < buf_end && x == 0xff) @@ -1373,13 +1356,14 @@ int ff_mjpeg_decode_frame(AVCodecContext *avctx, } } } - init_get_bits(&s->gb, s->buffer, (dst - s->buffer)*8); + *unescaped_buf_ptr = s->buffer; + *unescaped_buf_size = dst - s->buffer; - av_log(avctx, AV_LOG_DEBUG, "escaping removed %td bytes\n", - (buf_end - buf_ptr) - (dst - s->buffer)); + av_log(s->avctx, AV_LOG_DEBUG, "escaping removed %td bytes\n", + (buf_end - *buf_ptr) - (dst - s->buffer)); } else if(start_code == SOS && s->ls){ - const uint8_t *src = buf_ptr; + const uint8_t *src = *buf_ptr; uint8_t *dst = s->buffer; int bit_count = 0; int t = 0, b = 0; @@ -1415,10 +1399,46 @@ int ff_mjpeg_decode_frame(AVCodecContext *avctx, } flush_put_bits(&pb); - init_get_bits(&s->gb, dst, bit_count); + *unescaped_buf_ptr = dst; + *unescaped_buf_size = (bit_count + 7) >> 3; } else - init_get_bits(&s->gb, buf_ptr, (buf_end - buf_ptr)*8); + { + *unescaped_buf_ptr = *buf_ptr; + *unescaped_buf_size = buf_end - *buf_ptr; + } + + return start_code; +} + +int ff_mjpeg_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + int buf_size = avpkt->size; + MJpegDecodeContext *s = avctx->priv_data; + const uint8_t *buf_end, *buf_ptr; + const uint8_t *unescaped_buf_ptr; + int unescaped_buf_size; + int start_code; + AVFrame *picture = data; + + s->got_picture = 0; // picture from previous image can not be reused + buf_ptr = buf; + buf_end = buf + buf_size; + while (buf_ptr < buf_end) { + /* find start next marker */ + start_code = ff_mjpeg_find_marker(s, &buf_ptr, buf_end, + &unescaped_buf_ptr, &unescaped_buf_size); + { + /* EOF */ + if (start_code < 0) { + goto the_end; + } else { + av_log(avctx, AV_LOG_DEBUG, "marker=%x avail_size_in_buf=%td\n", start_code, buf_end - buf_ptr); + + init_get_bits(&s->gb, unescaped_buf_ptr, unescaped_buf_size*8); s->start_code = start_code; if(s->avctx->debug & FF_DEBUG_STARTCODE){ diff --git a/libavcodec/mjpegdec.h b/libavcodec/mjpegdec.h index 63bcb93046..72fe6fa088 100644 --- a/libavcodec/mjpegdec.h +++ b/libavcodec/mjpegdec.h @@ -117,5 +117,8 @@ int ff_mjpeg_decode_dht(MJpegDecodeContext *s); int ff_mjpeg_decode_sof(MJpegDecodeContext *s); int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask, const AVFrame *reference); +int ff_mjpeg_find_marker(MJpegDecodeContext *s, + const uint8_t **buf_ptr, const uint8_t *buf_end, + const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size); #endif /* AVCODEC_MJPEGDEC_H */ |