static int dv_decode_video_segment(AVCodecContext *avctx, void *arg) { DVVideoContext *s = avctx->priv_data; DVwork_chunk *work_chunk = arg; int quant, dc, dct_mode, class1, j; int mb_index, mb_x, mb_y, last_index; int y_stride, linesize; DCTELEM *block, *block1; int c_offset; uint8_t *y_ptr; const uint8_t *buf_ptr; PutBitContext pb, vs_pb; GetBitContext gb; BlockInfo mb_data[5 * DV_MAX_BPM], *mb, *mb1; LOCAL_ALIGNED_16(DCTELEM, sblock, [5*DV_MAX_BPM], [64]); LOCAL_ALIGNED_16(uint8_t, mb_bit_buffer, [ 80 + FF_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */ LOCAL_ALIGNED_16(uint8_t, vs_bit_buffer, [5*80 + FF_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */ const int log2_blocksize = 3; int is_field_mode[5]; assert((((int)mb_bit_buffer) & 7) == 0); assert((((int)vs_bit_buffer) & 7) == 0); memset(sblock, 0, 5*DV_MAX_BPM*sizeof(*sblock)); /* pass 1: read DC and AC coefficients in blocks */ buf_ptr = &s->buf[work_chunk->buf_offset*80]; block1 = &sblock[0][0]; mb1 = mb_data; init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80); for (mb_index = 0; mb_index < 5; mb_index++, mb1 += s->sys->bpm, block1 += s->sys->bpm * 64) { /* skip header */ quant = buf_ptr[3] & 0x0f; buf_ptr += 4; init_put_bits(&pb, mb_bit_buffer, 80); mb = mb1; block = block1; is_field_mode[mb_index] = 0; for (j = 0; j < s->sys->bpm; j++) { last_index = s->sys->block_sizes[j]; init_get_bits(&gb, buf_ptr, last_index); /* get the DC */ dc = get_sbits(&gb, 9); dct_mode = get_bits1(&gb); class1 = get_bits(&gb, 2); if (DV_PROFILE_IS_HD(s->sys)) { mb->idct_put = s->idct_put[0]; mb->scan_table = s->dv_zigzag[0]; mb->factor_table = &s->sys->idct_factor[(j >= 4)*4*16*64 + class1*16*64 + quant*64]; is_field_mode[mb_index] |= !j && dct_mode; } else { mb->idct_put = s->idct_put[dct_mode && log2_blocksize == 3]; mb->scan_table = s->dv_zigzag[dct_mode]; mb->factor_table = &s->sys->idct_factor[(class1 == 3)*2*22*64 + dct_mode*22*64 + (quant + ff_dv_quant_offset[class1])*64]; } dc = dc << 2; /* convert to unsigned because 128 is not added in the standard IDCT */ dc += 1024; block[0] = dc; buf_ptr += last_index >> 3; mb->pos = 0; mb->partial_bit_count = 0; av_dlog(avctx, "MB block: %d, %d ", mb_index, j); dv_decode_ac(&gb, mb, block); /* write the remaining bits in a new buffer only if the block is finished */ if (mb->pos >= 64) bit_copy(&pb, &gb); block += 64; mb++; } /* pass 2: we can do it just after */ av_dlog(avctx, "***pass 2 size=%d MB#=%d\n", put_bits_count(&pb), mb_index); block = block1; mb = mb1; init_get_bits(&gb, mb_bit_buffer, put_bits_count(&pb)); put_bits32(&pb, 0); // padding must be zeroed flush_put_bits(&pb); for (j = 0; j < s->sys->bpm; j++, block += 64, mb++) { if (mb->pos < 64 && get_bits_left(&gb) > 0) { dv_decode_ac(&gb, mb, block); /* if still not finished, no need to parse other blocks */ if (mb->pos < 64) break; } } /* all blocks are finished, so the extra bytes can be used at the video segment level */ if (j >= s->sys->bpm) bit_copy(&vs_pb, &gb); } /* we need a pass over the whole video segment */ av_dlog(avctx, "***pass 3 size=%d\n", put_bits_count(&vs_pb)); block = &sblock[0][0]; mb = mb_data; init_get_bits(&gb, vs_bit_buffer, put_bits_count(&vs_pb)); put_bits32(&vs_pb, 0); // padding must be zeroed flush_put_bits(&vs_pb); for (mb_index = 0; mb_index < 5; mb_index++) { for (j = 0; j < s->sys->bpm; j++) { if (mb->pos < 64) { av_dlog(avctx, "start %d:%d\n", mb_index, j); dv_decode_ac(&gb, mb, block); } if (mb->pos >= 64 && mb->pos < 127) av_log(avctx, AV_LOG_ERROR, "AC EOB marker is absent pos=%d\n", mb->pos); block += 64; mb++; } } /* compute idct and place blocks */ block = &sblock[0][0]; mb = mb_data; for (mb_index = 0; mb_index < 5; mb_index++) { dv_calculate_mb_xy(s, work_chunk, mb_index, &mb_x, &mb_y); /* idct_put'ting luminance */ if ((s->sys->pix_fmt == PIX_FMT_YUV420P) || (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x >= (704 / 8)) || (s->sys->height >= 720 && mb_y != 134)) { y_stride = (s->picture.linesize[0] << ((!is_field_mode[mb_index]) * log2_blocksize)); } else { y_stride = (2 << log2_blocksize); } y_ptr = s->picture.data[0] + ((mb_y * s->picture.linesize[0] + mb_x) << log2_blocksize); linesize = s->picture.linesize[0] << is_field_mode[mb_index]; mb[0] .idct_put(y_ptr , linesize, block + 0*64); if (s->sys->video_stype == 4) { /* SD 422 */ mb[2].idct_put(y_ptr + (1 << log2_blocksize) , linesize, block + 2*64); } else { mb[1].idct_put(y_ptr + (1 << log2_blocksize) , linesize, block + 1*64); mb[2].idct_put(y_ptr + y_stride, linesize, block + 2*64); mb[3].idct_put(y_ptr + (1 << log2_blocksize) + y_stride, linesize, block + 3*64); } mb += 4; block += 4*64; /* idct_put'ting chrominance */ c_offset = (((mb_y >> (s->sys->pix_fmt == PIX_FMT_YUV420P)) * s->picture.linesize[1] + (mb_x >> ((s->sys->pix_fmt == PIX_FMT_YUV411P) ? 2 : 1))) << log2_blocksize); for (j = 2; j; j--) { uint8_t *c_ptr = s->picture.data[j] + c_offset; if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x >= (704 / 8)) { uint64_t aligned_pixels[64/8]; uint8_t *pixels = (uint8_t*)aligned_pixels; uint8_t *c_ptr1, *ptr1; int x, y; mb->idct_put(pixels, 8, block); for (y = 0; y < (1 << log2_blocksize); y++, c_ptr += s->picture.linesize[j], pixels += 8) { ptr1 = pixels + (1 << (log2_blocksize - 1)); c_ptr1 = c_ptr + (s->picture.linesize[j] << log2_blocksize); for (x = 0; x < (1 << (log2_blocksize - 1)); x++) { c_ptr[x] = pixels[x]; c_ptr1[x] = ptr1[x]; } } block += 64; mb++; } else { y_stride = (mb_y == 134) ? (1 << log2_blocksize) : s->picture.linesize[j] << ((!is_field_mode[mb_index]) * log2_blocksize); linesize = s->picture.linesize[j] << is_field_mode[mb_index]; (mb++)-> idct_put(c_ptr , linesize, block); block += 64; if (s->sys->bpm == 8) { (mb++)->idct_put(c_ptr + y_stride, linesize, block); block += 64; } } } } return 0; }