3 * Copyright (c) 2000, 2001 Fabrice Bellard
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #include "libavutil/attributes.h"
29 #include "libavutil/avassert.h"
30 #include "libavutil/timecode.h"
34 #include "mpegvideo.h"
35 #include "error_resilience.h"
37 #include "mpeg12data.h"
38 #include "bytestream.h"
39 #include "vdpau_internal.h"
42 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
44 static const uint8_t table_mb_ptype[7][2] = {
45 { 3, 5 }, // 0x01 MB_INTRA
46 { 1, 2 }, // 0x02 MB_PAT
47 { 1, 3 }, // 0x08 MB_FOR
48 { 1, 1 }, // 0x0A MB_FOR|MB_PAT
49 { 1, 6 }, // 0x11 MB_QUANT|MB_INTRA
50 { 1, 5 }, // 0x12 MB_QUANT|MB_PAT
51 { 2, 5 }, // 0x1A MB_QUANT|MB_FOR|MB_PAT
54 static const uint8_t table_mb_btype[11][2] = {
55 { 3, 5 }, // 0x01 MB_INTRA
56 { 2, 3 }, // 0x04 MB_BACK
57 { 3, 3 }, // 0x06 MB_BACK|MB_PAT
58 { 2, 4 }, // 0x08 MB_FOR
59 { 3, 4 }, // 0x0A MB_FOR|MB_PAT
60 { 2, 2 }, // 0x0C MB_FOR|MB_BACK
61 { 3, 2 }, // 0x0E MB_FOR|MB_BACK|MB_PAT
62 { 1, 6 }, // 0x11 MB_QUANT|MB_INTRA
63 { 2, 6 }, // 0x16 MB_QUANT|MB_BACK|MB_PAT
64 { 3, 6 }, // 0x1A MB_QUANT|MB_FOR|MB_PAT
65 { 2, 5 }, // 0x1E MB_QUANT|MB_FOR|MB_BACK|MB_PAT
68 #define INIT_2D_VLC_RL(rl, static_size)\
70 static RL_VLC_ELEM rl_vlc_table[static_size];\
71 rl.rl_vlc[0] = rl_vlc_table;\
72 init_2d_vlc_rl(&rl, static_size);\
75 static av_cold void init_2d_vlc_rl(RLTable *rl, unsigned static_size)
78 VLC_TYPE table[680][2] = {{0}};
79 VLC vlc = { .table = table, .table_allocated = static_size };
80 av_assert0(static_size <= FF_ARRAY_ELEMS(table));
81 init_vlc(&vlc, TEX_VLC_BITS, rl->n + 2, &rl->table_vlc[0][1], 4, 2, &rl->table_vlc[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
83 for (i = 0; i < vlc.table_size; i++) {
84 int code = vlc.table[i][0];
85 int len = vlc.table[i][1];
88 if (len == 0) { // illegal code
91 } else if (len<0) { //more bits needed
95 if (code == rl->n) { //esc
98 } else if (code == rl->n+1) { //eob
102 run = rl->table_run [code] + 1;
103 level = rl->table_level[code];
106 rl->rl_vlc[0][i].len = len;
107 rl->rl_vlc[0][i].level = level;
108 rl->rl_vlc[0][i].run = run;
112 av_cold void ff_mpeg12_common_init(MpegEncContext *s)
115 s->y_dc_scale_table =
116 s->c_dc_scale_table = ff_mpeg2_dc_scale_table[s->intra_dc_precision];
120 void ff_mpeg1_clean_buffers(MpegEncContext *s)
122 s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
123 s->last_dc[1] = s->last_dc[0];
124 s->last_dc[2] = s->last_dc[0];
125 memset(s->last_mv, 0, sizeof(s->last_mv));
129 /******************************************/
135 VLC ff_dc_chroma_vlc;
142 av_cold void ff_mpeg12_init_vlcs(void)
149 INIT_VLC_STATIC(&ff_dc_lum_vlc, DC_VLC_BITS, 12,
150 ff_mpeg12_vlc_dc_lum_bits, 1, 1,
151 ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
152 INIT_VLC_STATIC(&ff_dc_chroma_vlc, DC_VLC_BITS, 12,
153 ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
154 ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
155 INIT_VLC_STATIC(&ff_mv_vlc, MV_VLC_BITS, 17,
156 &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
157 &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
158 INIT_VLC_STATIC(&ff_mbincr_vlc, MBINCR_VLC_BITS, 36,
159 &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
160 &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
161 INIT_VLC_STATIC(&ff_mb_pat_vlc, MB_PAT_VLC_BITS, 64,
162 &ff_mpeg12_mbPatTable[0][1], 2, 1,
163 &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
165 INIT_VLC_STATIC(&ff_mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
166 &table_mb_ptype[0][1], 2, 1,
167 &table_mb_ptype[0][0], 2, 1, 64);
168 INIT_VLC_STATIC(&ff_mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
169 &table_mb_btype[0][1], 2, 1,
170 &table_mb_btype[0][0], 2, 1, 64);
171 ff_init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
172 ff_init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
174 INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
175 INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
180 * Find the end of the current frame in the bitstream.
181 * @return the position of the first byte of the next frame, or -1
183 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
186 uint32_t state = pc->state;
188 /* EOF considered as end of frame */
194 1 first_SEQEXT -> 0/2
195 2 first field start -> 3/0
196 3 second_SEQEXT -> 2/0
200 for (i = 0; i < buf_size; i++) {
201 av_assert1(pc->frame_start_found >= 0 && pc->frame_start_found <= 4);
202 if (pc->frame_start_found & 1) {
203 if (state == EXT_START_CODE && (buf[i] & 0xF0) != 0x80)
204 pc->frame_start_found--;
205 else if (state == EXT_START_CODE + 2) {
206 if ((buf[i] & 3) == 3)
207 pc->frame_start_found = 0;
209 pc->frame_start_found = (pc->frame_start_found + 1) & 3;
213 i = avpriv_find_start_code(buf + i, buf + buf_size, &state) - buf - 1;
214 if (pc->frame_start_found == 0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE) {
216 pc->frame_start_found = 4;
218 if (state == SEQ_END_CODE) {
219 pc->frame_start_found = 0;
223 if (pc->frame_start_found == 2 && state == SEQ_START_CODE)
224 pc->frame_start_found = 0;
225 if (pc->frame_start_found < 4 && state == EXT_START_CODE)
226 pc->frame_start_found++;
227 if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) {
228 if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) {
229 pc->frame_start_found = 0;
234 if (pc->frame_start_found == 0 && s && state == PICTURE_START_CODE) {
235 ff_fetch_timestamp(s, i - 3, 1);
240 return END_NOT_FOUND;