static int read_extra_header(FFV1Context *f) { RangeCoder *const c = &f->c; uint8_t state[CONTEXT_SIZE]; int i, j, k, ret; uint8_t state2[32][CONTEXT_SIZE]; unsigned crc = 0; memset(state2, 128, sizeof(state2)); memset(state, 128, sizeof(state)); ff_init_range_decoder(c, f->avctx->extradata, f->avctx->extradata_size); ff_build_rac_states(c, 0.05 * (1LL << 32), 256 - 8); f->version = get_symbol(c, state, 0); if (f->version < 2) { av_log(f->avctx, AV_LOG_ERROR, "Invalid version in global header\n"); return AVERROR_INVALIDDATA; } if (f->version > 2) { c->bytestream_end -= 4; f->micro_version = get_symbol(c, state, 0); if (f->micro_version < 0) return AVERROR_INVALIDDATA; } f->ac = f->avctx->coder_type = get_symbol(c, state, 0); if (f->ac > 1) { for (i = 1; i < 256; i++) f->state_transition[i] = get_symbol(c, state, 1) + c->one_state[i]; } f->colorspace = get_symbol(c, state, 0); //YUV cs type f->avctx->bits_per_raw_sample = get_symbol(c, state, 0); f->chroma_planes = get_rac(c, state); f->chroma_h_shift = get_symbol(c, state, 0); f->chroma_v_shift = get_symbol(c, state, 0); f->transparency = get_rac(c, state); f->plane_count = 1 + (f->chroma_planes || f->version<4) + f->transparency; f->num_h_slices = 1 + get_symbol(c, state, 0); f->num_v_slices = 1 + get_symbol(c, state, 0); if (f->chroma_h_shift > 4U || f->chroma_v_shift > 4U) { av_log(f->avctx, AV_LOG_ERROR, "chroma shift parameters %d %d are invalid\n", f->chroma_h_shift, f->chroma_v_shift); return AVERROR_INVALIDDATA; } if (f->num_h_slices > (unsigned)f->width || !f->num_h_slices || f->num_v_slices > (unsigned)f->height || !f->num_v_slices ) { av_log(f->avctx, AV_LOG_ERROR, "slice count invalid\n"); return AVERROR_INVALIDDATA; } f->quant_table_count = get_symbol(c, state, 0); if (f->quant_table_count > (unsigned)MAX_QUANT_TABLES) return AVERROR_INVALIDDATA; for (i = 0; i < f->quant_table_count; i++) { f->context_count[i] = read_quant_tables(c, f->quant_tables[i]); if (f->context_count[i] < 0) { av_log(f->avctx, AV_LOG_ERROR, "read_quant_table error\n"); return AVERROR_INVALIDDATA; } } if ((ret = ff_ffv1_allocate_initial_states(f)) < 0) return ret; for (i = 0; i < f->quant_table_count; i++) if (get_rac(c, state)) { for (j = 0; j < f->context_count[i]; j++) for (k = 0; k < CONTEXT_SIZE; k++) { int pred = j ? f->initial_states[i][j - 1][k] : 128; f->initial_states[i][j][k] = (pred + get_symbol(c, state2[k], 1)) & 0xFF; } } if (f->version > 2) { f->ec = get_symbol(c, state, 0); if (f->micro_version > 2) f->intra = get_symbol(c, state, 0); } if (f->version > 2) { unsigned v; v = av_crc(av_crc_get_table(AV_CRC_32_IEEE), 0, f->avctx->extradata, f->avctx->extradata_size); if (v || f->avctx->extradata_size < 4) { av_log(f->avctx, AV_LOG_ERROR, "CRC mismatch %X!\n", v); return AVERROR_INVALIDDATA; } crc = AV_RB32(f->avctx->extradata + f->avctx->extradata_size - 4); } if (f->avctx->debug & FF_DEBUG_PICT_INFO) av_log(f->avctx, AV_LOG_DEBUG, "global: ver:%d.%d, coder:%d, colorspace: %d bpr:%d chroma:%d(%d:%d), alpha:%d slices:%dx%d qtabs:%d ec:%d intra:%d CRC:0x%08X\n", f->version, f->micro_version, f->ac, f->colorspace, f->avctx->bits_per_raw_sample, f->chroma_planes, f->chroma_h_shift, f->chroma_v_shift, f->transparency, f->num_h_slices, f->num_v_slices, f->quant_table_count, f->ec, f->intra, crc ); return 0; }