int ff_hevc_decode_extradata(const uint8_t *data, int size, HEVCParamSets *ps, int *is_nalff, int *nal_length_size, int err_recognition, void *logctx) { int ret = 0; GetByteContext gb; bytestream2_init(&gb, data, size); if (size > 3 && (data[0] || data[1] || data[2] > 1)) { /* It seems the extradata is encoded as hvcC format. * Temporarily, we support configurationVersion==0 until 14496-15 3rd * is finalized. When finalized, configurationVersion will be 1 and we * can recognize hvcC by checking if avctx->extradata[0]==1 or not. */ int i, j, num_arrays, nal_len_size; *is_nalff = 1; bytestream2_skip(&gb, 21); nal_len_size = (bytestream2_get_byte(&gb) & 3) + 1; num_arrays = bytestream2_get_byte(&gb); /* nal units in the hvcC always have length coded with 2 bytes, * so put a fake nal_length_size = 2 while parsing them */ *nal_length_size = 2; /* Decode nal units from hvcC. */ for (i = 0; i < num_arrays; i++) { int type = bytestream2_get_byte(&gb) & 0x3f; int cnt = bytestream2_get_be16(&gb); for (j = 0; j < cnt; j++) { // +2 for the nal size field int nalsize = bytestream2_peek_be16(&gb) + 2; if (bytestream2_get_bytes_left(&gb) < nalsize) { av_log(logctx, AV_LOG_ERROR, "Invalid NAL unit size in extradata.\n"); return AVERROR_INVALIDDATA; } ret = hevc_decode_nal_units(gb.buffer, nalsize, ps, *is_nalff, *nal_length_size, logctx); if (ret < 0) { av_log(logctx, AV_LOG_ERROR, "Decoding nal unit %d %d from hvcC failed\n", type, i); return ret; } bytestream2_skip(&gb, nalsize); } } /* Now store right nal length size, that will be used to parse * all other nals */ *nal_length_size = nal_len_size; } else { *is_nalff = 0; ret = hevc_decode_nal_units(data, size, ps, *is_nalff, *nal_length_size, logctx); if (ret < 0) return ret; } return ret; }