-static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size,
- int parse_extradata);
-
-/* There are (invalid) samples in the wild with mp4-style extradata, where the
- * parameter sets are stored unescaped (i.e. as RBSP).
- * This function catches the parameter set decoding failure and tries again
- * after escaping it */
-static int decode_extradata_ps_mp4(H264Context *h, const uint8_t *buf, int buf_size)
-{
- int ret;
-
- ret = decode_nal_units(h, buf, buf_size, 1);
- if (ret < 0 && !(h->avctx->err_recognition & AV_EF_EXPLODE)) {
- GetByteContext gbc;
- PutByteContext pbc;
- uint8_t *escaped_buf;
- int escaped_buf_size;
-
- av_log(h->avctx, AV_LOG_WARNING,
- "SPS decoding failure, trying again after escaping the NAL\n");
-
- if (buf_size / 2 >= (INT16_MAX - AV_INPUT_BUFFER_PADDING_SIZE) / 3)
- return AVERROR(ERANGE);
- escaped_buf_size = buf_size * 3 / 2 + AV_INPUT_BUFFER_PADDING_SIZE;
- escaped_buf = av_mallocz(escaped_buf_size);
- if (!escaped_buf)
- return AVERROR(ENOMEM);
-
- bytestream2_init(&gbc, buf, buf_size);
- bytestream2_init_writer(&pbc, escaped_buf, escaped_buf_size);
-
- while (bytestream2_get_bytes_left(&gbc)) {
- if (bytestream2_get_bytes_left(&gbc) >= 3 &&
- bytestream2_peek_be24(&gbc) <= 3) {
- bytestream2_put_be24(&pbc, 3);
- bytestream2_skip(&gbc, 2);
- } else
- bytestream2_put_byte(&pbc, bytestream2_get_byte(&gbc));
- }
-
- escaped_buf_size = bytestream2_tell_p(&pbc);
- AV_WB16(escaped_buf, escaped_buf_size - 2);
-
- ret = decode_nal_units(h, escaped_buf, escaped_buf_size, 1);
- av_freep(&escaped_buf);
- if (ret < 0)
- return ret;
- }
-
- return 0;
-}
-
-int ff_h264_decode_extradata(H264Context *h, const uint8_t *buf, int size)
-{
- AVCodecContext *avctx = h->avctx;
- int ret;
-
- if (!buf || size <= 0)
- return -1;
-
- if (buf[0] == 1) {
- int i, cnt, nalsize;
- const unsigned char *p = buf;
-
- h->is_avc = 1;
-
- if (size < 7) {
- av_log(avctx, AV_LOG_ERROR,
- "avcC %d too short\n", size);
- return AVERROR_INVALIDDATA;
- }
- /* sps and pps in the avcC always have length coded with 2 bytes,
- * so put a fake nal_length_size = 2 while parsing them */
- h->nal_length_size = 2;
- // Decode sps from avcC
- cnt = *(p + 5) & 0x1f; // Number of sps
- p += 6;
- for (i = 0; i < cnt; i++) {
- nalsize = AV_RB16(p) + 2;
- if(nalsize > size - (p-buf))
- return AVERROR_INVALIDDATA;
- ret = decode_extradata_ps_mp4(h, p, nalsize);
- if (ret < 0) {
- av_log(avctx, AV_LOG_ERROR,
- "Decoding sps %d from avcC failed\n", i);
- return ret;
- }
- p += nalsize;
- }
- // Decode pps from avcC
- cnt = *(p++); // Number of pps
- for (i = 0; i < cnt; i++) {
- nalsize = AV_RB16(p) + 2;
- if(nalsize > size - (p-buf))
- return AVERROR_INVALIDDATA;
- ret = decode_extradata_ps_mp4(h, p, nalsize);
- if (ret < 0) {
- av_log(avctx, AV_LOG_ERROR,
- "Decoding pps %d from avcC failed\n", i);
- return ret;
- }
- p += nalsize;
- }
- // Store right nal length size that will be used to parse all other nals
- h->nal_length_size = (buf[4] & 0x03) + 1;
- } else {
- h->is_avc = 0;
- ret = decode_nal_units(h, buf, size, 1);
- if (ret < 0)
- return ret;
- }
- return size;
-}
-