static int parse(AVCodecParserContext *ctx, AVCodecContext *avctx, const uint8_t **out_data, int *out_size, const uint8_t *data, int size) { VP9ParseContext *s = ctx->priv_data; int marker; if (size <= 0) { *out_size = 0; *out_data = data; return 0; } if (s->n_frames > 0) { *out_data = data; *out_size = s->size[--s->n_frames]; parse_frame(ctx, *out_data, *out_size); return s->n_frames > 0 ? *out_size : size /* i.e. include idx tail */; } marker = data[size - 1]; if ((marker & 0xe0) == 0xc0) { int nbytes = 1 + ((marker >> 3) & 0x3); int n_frames = 1 + (marker & 0x7), idx_sz = 2 + n_frames * nbytes; if (size >= idx_sz && data[size - idx_sz] == marker) { const uint8_t *idx = data + size + 1 - idx_sz; int first = 1; switch (nbytes) { #define case_n(a, rd) \ case a: \ while (n_frames--) { \ int sz = rd; \ idx += a; \ if (sz > size) { \ s->n_frames = 0; \ av_log(avctx, AV_LOG_ERROR, \ "Superframe packet size too big: %d > %d\n", \ sz, size); \ return AVERROR_INVALIDDATA; \ } \ if (first) { \ first = 0; \ *out_data = data; \ *out_size = sz; \ s->n_frames = n_frames; \ } else { \ s->size[n_frames] = sz; \ } \ data += sz; \ size -= sz; \ } \ parse_frame(ctx, *out_data, *out_size); \ return *out_size case_n(1, *idx); case_n(2, AV_RL16(idx)); case_n(3, AV_RL24(idx)); case_n(4, AV_RL32(idx)); } } } *out_data = data; *out_size = size; parse_frame(ctx, data, size); return size; }