Merge commit '83b2b34d06e74cc8775ba3d833f9782505e17539'
authorJames Almer <jamrial@gmail.com>
Fri, 20 Oct 2017 22:04:53 +0000 (19:04 -0300)
committerJames Almer <jamrial@gmail.com>
Fri, 20 Oct 2017 22:04:53 +0000 (19:04 -0300)
* commit '83b2b34d06e74cc8775ba3d833f9782505e17539':
  h2645_parse: use the bytestream2 API for packet splitting

Merged-by: James Almer <jamrial@gmail.com>
1  2 
libavcodec/h2645_parse.c

@@@ -26,7 -26,7 +26,8 @@@
  #include "libavutil/intreadwrite.h"
  #include "libavutil/mem.h"
  
+ #include "bytestream.h"
 +#include "hevc.h"
  #include "h2645_parse.h"
  
  int ff_h2645_extract_rbsp(const uint8_t *src, int length,
@@@ -247,61 -196,81 +248,75 @@@ static int h264_parse_nal_header(H2645N
      return 1;
  }
  
+ static int find_next_start_code(const uint8_t *buf, const uint8_t *next_avc)
+ {
+     int i = 0;
+     if (buf + 3 >= next_avc)
+         return next_avc - buf;
+     while (buf + i + 3 < next_avc) {
+         if (buf[i] == 0 && buf[i + 1] == 0 && buf[i + 2] == 1)
+             break;
+         i++;
+     }
+     return i + 3;
+ }
  int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
                            void *logctx, int is_nalff, int nal_length_size,
 -                          enum AVCodecID codec_id)
 +                          enum AVCodecID codec_id, int small_padding)
  {
+     GetByteContext bc;
      int consumed, ret = 0;
-     const uint8_t *next_avc = is_nalff ? buf : buf + length;
 -    size_t next_avc = is_nalff ? 0 : length;
++    int next_avc = is_nalff ? 0 : length;
+     bytestream2_init(&bc, buf, length);
  
      pkt->nb_nals = 0;
-     while (length >= 4) {
+     while (bytestream2_get_bytes_left(&bc) >= 4) {
          H2645NAL *nal;
          int extract_length = 0;
          int skip_trailing_zeros = 1;
  
-         if (buf == next_avc) {
 -        /*
 -         * Only parse an AVC1 length field if one is expected at the current
 -         * buffer position. There are unfortunately streams with multiple
 -         * NAL units covered by the length field. Those NAL units are delimited
 -         * by Annex B start code prefixes. ff_h2645_extract_rbsp() detects it
 -         * correctly and consumes only the first NAL unit. The additional NAL
 -         * units are handled here in the Annex B parsing code.
 -         */
+         if (bytestream2_tell(&bc) == next_avc) {
 -            int i;
 -            for (i = 0; i < nal_length_size; i++)
 -                extract_length = (extract_length << 8) | bytestream2_get_byte(&bc);
 -
 -            if (extract_length > bytestream2_get_bytes_left(&bc)) {
 -                av_log(logctx, AV_LOG_ERROR,
 -                       "Invalid NAL unit size (%d > %d).\n",
 -                       extract_length, bytestream2_get_bytes_left(&bc));
 -                return AVERROR_INVALIDDATA;
 -            }
 -            // keep track of the next AVC1 length field
 +            int i = 0;
 +            extract_length = get_nalsize(nal_length_size,
-                                          buf, length, &i, logctx);
++                                         bc.buffer, bytestream2_get_bytes_left(&bc), &i, logctx);
 +            if (extract_length < 0)
 +                return extract_length;
 +
-             buf    += nal_length_size;
-             length -= nal_length_size;
++            bytestream2_skip(&bc, nal_length_size);
 +
-             next_avc = buf + extract_length;
+             next_avc = bytestream2_tell(&bc) + extract_length;
          } else {
-             if (buf > next_avc)
 -            /*
 -             * expected to return immediately except for streams with mixed
 -             * NAL unit coding
 -             */
 -            int buf_index = find_next_start_code(bc.buffer, buf + next_avc);
++            int buf_index;
++
++            if (bytestream2_tell(&bc) > next_avc)
 +                av_log(logctx, AV_LOG_WARNING, "Exceeded next NALFF position, re-syncing.\n");
 +
 +            /* search start code */
-             while (buf[0] != 0 || buf[1] != 0 || buf[2] != 1) {
-                 ++buf;
-                 --length;
-                 if (length < 4) {
-                     if (pkt->nb_nals > 0) {
-                         // No more start codes: we discarded some irrelevant
-                         // bytes at the end of the packet.
-                         return 0;
-                     } else {
-                         av_log(logctx, AV_LOG_ERROR, "No start code is found.\n");
-                         return AVERROR_INVALIDDATA;
-                     }
-                 } else if (buf >= (next_avc - 3))
-                     break;
++            buf_index = find_next_start_code(bc.buffer, buf + next_avc);
+             bytestream2_skip(&bc, buf_index);
 -            /*
 -             * break if an AVC1 length field is expected at the current buffer
 -             * position
 -             */
 -            if (bytestream2_tell(&bc) == next_avc)
 -                continue;
++            if (!bytestream2_get_bytes_left(&bc)) {
++                if (pkt->nb_nals > 0) {
++                    // No more start codes: we discarded some irrelevant
++                    // bytes at the end of the packet.
++                    return 0;
++                } else {
++                    av_log(logctx, AV_LOG_ERROR, "No start code is found.\n");
++                    return AVERROR_INVALIDDATA;
++                }
 +            }
 +
-             buf           += 3;
-             length        -= 3;
-             extract_length = FFMIN(length, next_avc - buf);
++            extract_length = FFMIN(bytestream2_get_bytes_left(&bc), next_avc - bytestream2_tell(&bc));
  
-             if (buf >= next_avc) {
 -            if (bytestream2_get_bytes_left(&bc) > 0) {
 -                extract_length = bytestream2_get_bytes_left(&bc);
 -            } else if (pkt->nb_nals == 0) {
 -                av_log(logctx, AV_LOG_ERROR, "No NAL unit found\n");
 -                return AVERROR_INVALIDDATA;
 -            } else {
 -                break;
++            if (bytestream2_tell(&bc) >= next_avc) {
 +                /* skip to the start of the next NAL */
-                 int offset = next_avc - buf;
-                 buf    += offset;
-                 length -= offset;
++                bytestream2_skip(&bc, next_avc - bytestream2_tell(&bc));
 +                continue;
              }
          }
  
  
              pkt->nals = tmp;
              memset(pkt->nals + pkt->nals_allocated, 0,
 -                   (new_size - pkt->nals_allocated) * sizeof(*tmp));
 +                   (new_size - pkt->nals_allocated) * sizeof(*pkt->nals));
 +
 +            nal = &pkt->nals[pkt->nb_nals];
 +            nal->skipped_bytes_pos_size = 1024; // initial buffer size
 +            nal->skipped_bytes_pos = av_malloc_array(nal->skipped_bytes_pos_size, sizeof(*nal->skipped_bytes_pos));
 +            if (!nal->skipped_bytes_pos)
 +                return AVERROR(ENOMEM);
 +
              pkt->nals_allocated = new_size;
          }
 -        nal = &pkt->nals[pkt->nb_nals++];
 +        nal = &pkt->nals[pkt->nb_nals];
  
-         consumed = ff_h2645_extract_rbsp(buf, extract_length, nal, small_padding);
 -        consumed = ff_h2645_extract_rbsp(bc.buffer, extract_length, nal);
++        consumed = ff_h2645_extract_rbsp(bc.buffer, extract_length, nal, small_padding);
          if (consumed < 0)
              return consumed;
  
 +        if (is_nalff && (extract_length != consumed) && extract_length)
 +            av_log(logctx, AV_LOG_DEBUG,
 +                   "NALFF: Consumed only %d bytes instead of %d\n",
 +                   consumed, extract_length);
 +
 +        pkt->nb_nals++;
 +
+         bytestream2_skip(&bc, consumed);
          /* see commit 3566042a0 */
-         if (consumed < length - 3 &&
-             buf[consumed]     == 0x00 && buf[consumed + 1] == 0x00 &&
-             buf[consumed + 2] == 0x01 && buf[consumed + 3] == 0xE0)
+         if (bytestream2_get_bytes_left(&bc) >= 4 &&
+             bytestream2_peek_be32(&bc) == 0x000001E0)
              skip_trailing_zeros = 0;
  
          nal->size_bits = get_bit_length(nal, skip_trailing_zeros);