1 /*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #include <stdint.h>
20
21 // for FF_QSCALE_TYPE_*
22 #include "libavcodec/internal.h"
23
24 #include "libavutil/frame.h"
25 #include "libavutil/mem.h"
26 #include "libavutil/video_enc_params.h"
27
28 #include "qp_table.h"
29
ff_qp_table_extract(AVFrame * frame,int8_t ** table,int * table_w,int * table_h,int * qscale_type)30 int ff_qp_table_extract(AVFrame *frame, int8_t **table, int *table_w, int *table_h,
31 int *qscale_type)
32 {
33 AVFrameSideData *sd;
34 AVVideoEncParams *par;
35 unsigned int mb_h = (frame->height + 15) / 16;
36 unsigned int mb_w = (frame->width + 15) / 16;
37 unsigned int nb_mb = mb_h * mb_w;
38 unsigned int block_idx;
39
40 *table = NULL;
41
42 sd = av_frame_get_side_data(frame, AV_FRAME_DATA_VIDEO_ENC_PARAMS);
43 if (!sd)
44 return 0;
45 par = (AVVideoEncParams*)sd->data;
46 if (par->type != AV_VIDEO_ENC_PARAMS_MPEG2 ||
47 (par->nb_blocks != 0 && par->nb_blocks != nb_mb))
48 return AVERROR(ENOSYS);
49
50 *table = av_malloc(nb_mb);
51 if (!*table)
52 return AVERROR(ENOMEM);
53 if (table_w)
54 *table_w = mb_w;
55 if (table_h)
56 *table_h = mb_h;
57 if (qscale_type)
58 *qscale_type = FF_QSCALE_TYPE_MPEG2;
59
60 if (par->nb_blocks == 0) {
61 memset(*table, par->qp, nb_mb);
62 return 0;
63 }
64
65 for (block_idx = 0; block_idx < nb_mb; block_idx++) {
66 AVVideoBlockParams *b = av_video_enc_params_block(par, block_idx);
67 (*table)[block_idx] = par->qp + b->delta_qp;
68 }
69
70 return 0;
71 }
72
73