]> rtime.felk.cvut.cz Git - frescor/ffmpeg.git/blobdiff - libavcodec/h264_parser.c
WMA: extend exponent range to 95
[frescor/ffmpeg.git] / libavcodec / h264_parser.c
index 515312c311ae51166fd408109b133048c5fe2f58..dabd475f9312c72276ee49ea1099a6d5e924ad0d 100644 (file)
  */
 
 /**
- * @file h264_parser.c
+ * @file libavcodec/h264_parser.c
  * H.264 / AVC / MPEG4 part10 parser.
  * @author Michael Niedermayer <michaelni@gmx.at>
  */
 
 #include "parser.h"
 #include "h264_parser.h"
+#include "h264data.h"
+#include "golomb.h"
 
 #include <assert.h>
 
@@ -49,10 +51,10 @@ int ff_h264_find_frame_end(H264Context *h, const uint8_t *buf, int buf_size)
          * and there should be FF_INPUT_BUFFER_PADDING_SIZE bytes at the end
          */
 #    if HAVE_FAST_64BIT
-            while(i<buf_size && !((~*(uint64_t*)(buf+i) & (*(uint64_t*)(buf+i) - 0x0101010101010101ULL)) & 0x8080808080808080ULL))
+            while(i<buf_size && !((~*(const uint64_t*)(buf+i) & (*(const uint64_t*)(buf+i) - 0x0101010101010101ULL)) & 0x8080808080808080ULL))
                 i+=8;
 #    else
-            while(i<buf_size && !((~*(uint32_t*)(buf+i) & (*(uint32_t*)(buf+i) - 0x01010101U)) & 0x80808080U))
+            while(i<buf_size && !((~*(const uint32_t*)(buf+i) & (*(const uint32_t*)(buf+i) - 0x01010101U)) & 0x80808080U))
                 i+=4;
 #    endif
 #endif
@@ -68,7 +70,7 @@ int ff_h264_find_frame_end(H264Context *h, const uint8_t *buf, int buf_size)
             else            state>>=1; //2->1, 1->0, 0->0
         }else if(state<=5){
             int v= buf[i] & 0x1F;
-            if(v==7 || v==8 || v==9){
+            if(v==6 || v==7 || v==8 || v==9){
                 if(pc->frame_start_found){
                     i++;
                     goto found;
@@ -96,6 +98,141 @@ found:
     return i-(state&5);
 }
 
+/*!
+ * Parse NAL units of found picture and decode some basic information.
+ *
+ * @param s parser context.
+ * @param avctx codec context.
+ * @param buf buffer with field/frame data.
+ * @param buf_size size of the buffer.
+ */
+static inline int parse_nal_units(AVCodecParserContext *s,
+                                  AVCodecContext *avctx,
+                                  const uint8_t *buf, int buf_size)
+{
+    H264Context *h = s->priv_data;
+    const uint8_t *buf_end = buf + buf_size;
+    unsigned int pps_id;
+    unsigned int slice_type;
+    int state = -1;
+    const uint8_t *ptr;
+
+    /* set some sane default values */
+    s->pict_type = FF_I_TYPE;
+    s->key_frame = 0;
+
+    h->s.avctx= avctx;
+    h->sei_recovery_frame_cnt = -1;
+    h->sei_dpb_output_delay         =  0;
+    h->sei_cpb_removal_delay        = -1;
+    h->sei_buffering_period_present =  0;
+
+    for(;;) {
+        int src_length, dst_length, consumed;
+        buf = ff_find_start_code(buf, buf_end, &state);
+        if(buf >= buf_end)
+            break;
+        --buf;
+        src_length = buf_end - buf;
+        switch (state & 0x1f) {
+        case NAL_SLICE:
+        case NAL_IDR_SLICE:
+            // Do not walk the whole buffer just to decode slice header
+            if (src_length > 20)
+                src_length = 20;
+            break;
+        }
+        ptr= ff_h264_decode_nal(h, buf, &dst_length, &consumed, src_length);
+        if (ptr==NULL || dst_length < 0)
+            break;
+
+        init_get_bits(&h->s.gb, ptr, 8*dst_length);
+        switch(h->nal_unit_type) {
+        case NAL_SPS:
+            ff_h264_decode_seq_parameter_set(h);
+            break;
+        case NAL_PPS:
+            ff_h264_decode_picture_parameter_set(h, h->s.gb.size_in_bits);
+            break;
+        case NAL_SEI:
+            ff_h264_decode_sei(h);
+            break;
+        case NAL_IDR_SLICE:
+            s->key_frame = 1;
+            /* fall through */
+        case NAL_SLICE:
+            get_ue_golomb(&h->s.gb);  // skip first_mb_in_slice
+            slice_type = get_ue_golomb_31(&h->s.gb);
+            s->pict_type = golomb_to_pict_type[slice_type % 5];
+            if (h->sei_recovery_frame_cnt >= 0) {
+                /* key frame, since recovery_frame_cnt is set */
+                s->key_frame = 1;
+            }
+            pps_id= get_ue_golomb(&h->s.gb);
+            if(pps_id>=MAX_PPS_COUNT) {
+                av_log(h->s.avctx, AV_LOG_ERROR, "pps_id out of range\n");
+                return -1;
+            }
+            if(!h->pps_buffers[pps_id]) {
+                av_log(h->s.avctx, AV_LOG_ERROR, "non-existing PPS referenced\n");
+                return -1;
+            }
+            h->pps= *h->pps_buffers[pps_id];
+            if(!h->sps_buffers[h->pps.sps_id]) {
+                av_log(h->s.avctx, AV_LOG_ERROR, "non-existing SPS referenced\n");
+                return -1;
+            }
+            h->sps = *h->sps_buffers[h->pps.sps_id];
+            h->frame_num = get_bits(&h->s.gb, h->sps.log2_max_frame_num);
+
+            if(h->sps.frame_mbs_only_flag){
+                h->s.picture_structure= PICT_FRAME;
+            }else{
+                if(get_bits1(&h->s.gb)) { //field_pic_flag
+                    h->s.picture_structure= PICT_TOP_FIELD + get_bits1(&h->s.gb); //bottom_field_flag
+                } else {
+                    h->s.picture_structure= PICT_FRAME;
+                }
+            }
+
+            if(h->sps.pic_struct_present_flag) {
+                switch (h->sei_pic_struct) {
+                    case SEI_PIC_STRUCT_TOP_FIELD:
+                    case SEI_PIC_STRUCT_BOTTOM_FIELD:
+                        s->repeat_pict = 0;
+                        break;
+                    case SEI_PIC_STRUCT_FRAME:
+                    case SEI_PIC_STRUCT_TOP_BOTTOM:
+                    case SEI_PIC_STRUCT_BOTTOM_TOP:
+                        s->repeat_pict = 1;
+                        break;
+                    case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
+                    case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
+                        s->repeat_pict = 2;
+                        break;
+                    case SEI_PIC_STRUCT_FRAME_DOUBLING:
+                        s->repeat_pict = 3;
+                        break;
+                    case SEI_PIC_STRUCT_FRAME_TRIPLING:
+                        s->repeat_pict = 5;
+                        break;
+                    default:
+                        s->repeat_pict = h->s.picture_structure == PICT_FRAME ? 1 : 0;
+                        break;
+                }
+            } else {
+                s->repeat_pict = h->s.picture_structure == PICT_FRAME ? 1 : 0;
+            }
+
+            return 0; /* no need to evaluate the rest */
+        }
+        buf += consumed;
+    }
+    /* didn't find a picture! */
+    av_log(h->s.avctx, AV_LOG_ERROR, "missing picture in access unit\n");
+    return -1;
+}
+
 static int h264_parse(AVCodecParserContext *s,
                       AVCodecContext *avctx,
                       const uint8_t **poutbuf, int *poutbuf_size,
@@ -120,6 +257,18 @@ static int h264_parse(AVCodecParserContext *s,
             assert(pc->last_index + next >= 0 );
             ff_h264_find_frame_end(h, &pc->buffer[pc->last_index + next], -next); //update state
         }
+
+        parse_nal_units(s, avctx, buf, buf_size);
+
+        if (h->sei_cpb_removal_delay >= 0) {
+            s->dts_sync_point    = h->sei_buffering_period_present;
+            s->dts_ref_dts_delta = h->sei_cpb_removal_delay;
+            s->pts_dts_delta     = h->sei_dpb_output_delay;
+        } else {
+            s->dts_sync_point    = INT_MIN;
+            s->dts_ref_dts_delta = INT_MIN;
+            s->pts_dts_delta     = INT_MIN;
+        }
     }
 
     *poutbuf = buf;
@@ -157,12 +306,12 @@ static void close(AVCodecParserContext *s)
     ParseContext *pc = &h->s.parse_context;
 
     av_free(pc->buffer);
+    ff_h264_free_context(h);
 }
 
 
 AVCodecParser h264_parser = {
-    { CODEC_ID_H264,
-      CODEC_ID_H264_VDPAU },
+    { CODEC_ID_H264 },
     sizeof(H264Context),
     NULL,
     h264_parse,