xref: /third_party/ffmpeg/libavcodec/wmv2enc.c (revision cabdff1a)
1/*
2 * Copyright (c) 2002 The FFmpeg Project
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#include "avcodec.h"
22#include "codec_internal.h"
23#include "h263.h"
24#include "mpegvideo.h"
25#include "mpegvideoenc.h"
26#include "msmpeg4.h"
27#include "msmpeg4enc.h"
28#include "msmpeg4data.h"
29#include "wmv2.h"
30#include "wmv2enc.h"
31
32typedef struct WMV2EncContext {
33    MSMPEG4EncContext msmpeg4;
34    WMV2Context common;
35    int j_type_bit;
36    int j_type;
37    int abt_flag;
38    int abt_type;
39    int per_mb_abt;
40    int mspel_bit;
41    int cbp_table_index;
42    int top_left_mv_flag;
43    int per_mb_rl_bit;
44} WMV2EncContext;
45
46static int encode_ext_header(WMV2EncContext *w)
47{
48    MpegEncContext *const s = &w->msmpeg4.s;
49    PutBitContext pb;
50    int code;
51
52    init_put_bits(&pb, s->avctx->extradata, s->avctx->extradata_size);
53
54    put_bits(&pb, 5, s->avctx->time_base.den / s->avctx->time_base.num); // yes 29.97 -> 29
55    put_bits(&pb, 11, FFMIN(s->bit_rate / 1024, 2047));
56
57    put_bits(&pb, 1, w->mspel_bit        = 1);
58    put_bits(&pb, 1, s->loop_filter);
59    put_bits(&pb, 1, w->abt_flag         = 1);
60    put_bits(&pb, 1, w->j_type_bit       = 1);
61    put_bits(&pb, 1, w->top_left_mv_flag = 0);
62    put_bits(&pb, 1, w->per_mb_rl_bit    = 1);
63    put_bits(&pb, 3, code                = 1);
64
65    flush_put_bits(&pb);
66
67    s->slice_height = s->mb_height / code;
68
69    return 0;
70}
71
72static av_cold int wmv2_encode_init(AVCodecContext *avctx)
73{
74    WMV2EncContext *const w = avctx->priv_data;
75    MpegEncContext *const s = &w->msmpeg4.s;
76
77    s->private_ctx = &w->common;
78    if (ff_mpv_encode_init(avctx) < 0)
79        return -1;
80
81    ff_wmv2_common_init(s);
82
83    avctx->extradata_size = 4;
84    avctx->extradata      = av_mallocz(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
85    if (!avctx->extradata)
86        return AVERROR(ENOMEM);
87
88    encode_ext_header(w);
89
90    return 0;
91}
92
93int ff_wmv2_encode_picture_header(MpegEncContext *s, int picture_number)
94{
95    WMV2EncContext *const w = (WMV2EncContext *) s;
96
97    put_bits(&s->pb, 1, s->pict_type - 1);
98    if (s->pict_type == AV_PICTURE_TYPE_I)
99        put_bits(&s->pb, 7, 0);
100    put_bits(&s->pb, 5, s->qscale);
101
102    s->dc_table_index  = 1;
103    s->mv_table_index  = 1; /* only if P-frame */
104    s->per_mb_rl_table = 0;
105    s->mspel           = 0;
106    w->per_mb_abt      = 0;
107    w->abt_type        = 0;
108    w->j_type          = 0;
109
110    av_assert0(s->flipflop_rounding);
111
112    if (s->pict_type == AV_PICTURE_TYPE_I) {
113        av_assert0(s->no_rounding == 1);
114        if (w->j_type_bit)
115            put_bits(&s->pb, 1, w->j_type);
116
117        if (w->per_mb_rl_bit)
118            put_bits(&s->pb, 1, s->per_mb_rl_table);
119
120        if (!s->per_mb_rl_table) {
121            ff_msmpeg4_code012(&s->pb, s->rl_chroma_table_index);
122            ff_msmpeg4_code012(&s->pb, s->rl_table_index);
123        }
124
125        put_bits(&s->pb, 1, s->dc_table_index);
126
127        s->inter_intra_pred = 0;
128    } else {
129        int cbp_index;
130
131        put_bits(&s->pb, 2, SKIP_TYPE_NONE);
132
133        ff_msmpeg4_code012(&s->pb, cbp_index = 0);
134        w->cbp_table_index = wmv2_get_cbp_table_index(s, cbp_index);
135
136        if (w->mspel_bit)
137            put_bits(&s->pb, 1, s->mspel);
138
139        if (w->abt_flag) {
140            put_bits(&s->pb, 1, w->per_mb_abt ^ 1);
141            if (!w->per_mb_abt)
142                ff_msmpeg4_code012(&s->pb, w->abt_type);
143        }
144
145        if (w->per_mb_rl_bit)
146            put_bits(&s->pb, 1, s->per_mb_rl_table);
147
148        if (!s->per_mb_rl_table) {
149            ff_msmpeg4_code012(&s->pb, s->rl_table_index);
150            s->rl_chroma_table_index = s->rl_table_index;
151        }
152        put_bits(&s->pb, 1, s->dc_table_index);
153        put_bits(&s->pb, 1, s->mv_table_index);
154
155        s->inter_intra_pred = 0; // (s->width * s->height < 320 * 240 && s->bit_rate <= II_BITRATE);
156    }
157    s->esc3_level_length = 0;
158    s->esc3_run_length   = 0;
159
160    return 0;
161}
162
163/* Nearly identical to wmv1 but that is just because we do not use the
164 * useless M$ crap features. It is duplicated here in case someone wants
165 * to add support for these crap features. */
166void ff_wmv2_encode_mb(MpegEncContext *s, int16_t block[6][64],
167                       int motion_x, int motion_y)
168{
169    WMV2EncContext *const w = (WMV2EncContext *) s;
170    int cbp, coded_cbp, i;
171    int pred_x, pred_y;
172    uint8_t *coded_block;
173
174    ff_msmpeg4_handle_slices(s);
175
176    if (!s->mb_intra) {
177        /* compute cbp */
178        cbp = 0;
179        for (i = 0; i < 6; i++)
180            if (s->block_last_index[i] >= 0)
181                cbp |= 1 << (5 - i);
182
183        put_bits(&s->pb,
184                 ff_wmv2_inter_table[w->cbp_table_index][cbp + 64][1],
185                 ff_wmv2_inter_table[w->cbp_table_index][cbp + 64][0]);
186
187        s->misc_bits += get_bits_diff(s);
188        /* motion vector */
189        ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
190        ff_msmpeg4_encode_motion(s, motion_x - pred_x,
191                                 motion_y - pred_y);
192        s->mv_bits += get_bits_diff(s);
193    } else {
194        /* compute cbp */
195        cbp       = 0;
196        coded_cbp = 0;
197        for (i = 0; i < 6; i++) {
198            int val, pred;
199            val  = (s->block_last_index[i] >= 1);
200            cbp |= val << (5 - i);
201            if (i < 4) {
202                /* predict value for close blocks only for luma */
203                pred         = ff_msmpeg4_coded_block_pred(s, i, &coded_block);
204                *coded_block = val;
205                val          = val ^ pred;
206            }
207            coded_cbp |= val << (5 - i);
208        }
209
210        if (s->pict_type == AV_PICTURE_TYPE_I)
211            put_bits(&s->pb,
212                     ff_msmp4_mb_i_table[coded_cbp][1],
213                     ff_msmp4_mb_i_table[coded_cbp][0]);
214        else
215            put_bits(&s->pb,
216                     ff_wmv2_inter_table[w->cbp_table_index][cbp][1],
217                     ff_wmv2_inter_table[w->cbp_table_index][cbp][0]);
218        put_bits(&s->pb, 1, 0);         /* no AC prediction yet */
219        if (s->inter_intra_pred) {
220            s->h263_aic_dir = 0;
221            put_bits(&s->pb,
222                     ff_table_inter_intra[s->h263_aic_dir][1],
223                     ff_table_inter_intra[s->h263_aic_dir][0]);
224        }
225        s->misc_bits += get_bits_diff(s);
226    }
227
228    for (i = 0; i < 6; i++)
229        ff_msmpeg4_encode_block(s, block[i], i);
230    if (s->mb_intra)
231        s->i_tex_bits += get_bits_diff(s);
232    else
233        s->p_tex_bits += get_bits_diff(s);
234}
235
236const FFCodec ff_wmv2_encoder = {
237    .p.name         = "wmv2",
238    .p.long_name    = NULL_IF_CONFIG_SMALL("Windows Media Video 8"),
239    .p.type         = AVMEDIA_TYPE_VIDEO,
240    .p.id           = AV_CODEC_ID_WMV2,
241    .p.priv_class   = &ff_mpv_enc_class,
242    .priv_data_size = sizeof(WMV2EncContext),
243    .init           = wmv2_encode_init,
244    FF_CODEC_ENCODE_CB(ff_mpv_encode_picture),
245    .close          = ff_mpv_encode_end,
246    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
247    .p.pix_fmts     = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
248                                                     AV_PIX_FMT_NONE },
249};
250