Line | Branch | Exec | Source |
---|---|---|---|
1 | /* | ||
2 | * H.261 decoder | ||
3 | * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> | ||
4 | * Copyright (c) 2004 Maarten Daniels | ||
5 | * | ||
6 | * This file is part of FFmpeg. | ||
7 | * | ||
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. | ||
12 | * | ||
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. | ||
17 | * | ||
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 | ||
21 | */ | ||
22 | |||
23 | /** | ||
24 | * @file | ||
25 | * H.261 decoder. | ||
26 | */ | ||
27 | |||
28 | #include "libavutil/mem_internal.h" | ||
29 | #include "libavutil/thread.h" | ||
30 | #include "avcodec.h" | ||
31 | #include "codec_internal.h" | ||
32 | #include "decode.h" | ||
33 | #include "get_bits.h" | ||
34 | #include "mpeg_er.h" | ||
35 | #include "mpegutils.h" | ||
36 | #include "mpegvideo.h" | ||
37 | #include "mpegvideodec.h" | ||
38 | #include "h261.h" | ||
39 | |||
40 | #define SLICE_OK 0 | ||
41 | #define SLICE_ERROR -1 | ||
42 | #define SLICE_END -2 ///<end marker found | ||
43 | |||
44 | #define H261_MBA_VLC_BITS 8 | ||
45 | #define H261_MTYPE_VLC_BITS 6 | ||
46 | #define H261_MV_VLC_BITS 7 | ||
47 | #define H261_CBP_VLC_BITS 9 | ||
48 | #define TCOEFF_VLC_BITS 9 | ||
49 | #define MBA_STUFFING 33 | ||
50 | #define MBA_STARTCODE 34 | ||
51 | |||
52 | static VLCElem h261_mba_vlc[540]; | ||
53 | static VLCElem h261_mtype_vlc[80]; | ||
54 | static VLCElem h261_mv_vlc[144]; | ||
55 | static VLCElem h261_cbp_vlc[512]; | ||
56 | |||
57 | typedef struct H261DecContext { | ||
58 | MpegEncContext s; | ||
59 | |||
60 | GetBitContext gb; | ||
61 | |||
62 | H261Context common; | ||
63 | |||
64 | int current_mba; | ||
65 | int mba_diff; | ||
66 | int current_mv_x; | ||
67 | int current_mv_y; | ||
68 | int gob_number; | ||
69 | int gob_start_code_skipped; // 1 if gob start code is already read before gob header is read | ||
70 | |||
71 | DECLARE_ALIGNED_32(int16_t, block)[6][64]; | ||
72 | } H261DecContext; | ||
73 | |||
74 | 7 | static av_cold void h261_decode_init_static(void) | |
75 | { | ||
76 | 7 | VLC_INIT_STATIC_TABLE(h261_mba_vlc, H261_MBA_VLC_BITS, 35, | |
77 | ff_h261_mba_bits, 1, 1, | ||
78 | ff_h261_mba_code, 1, 1, 0); | ||
79 | 7 | VLC_INIT_STATIC_SPARSE_TABLE(h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10, | |
80 | ff_h261_mtype_bits, 1, 1, | ||
81 | ff_h261_mtype_code, 1, 1, | ||
82 | ff_h261_mtype_map, 2, 2, 0); | ||
83 | 7 | VLC_INIT_STATIC_TABLE(h261_mv_vlc, H261_MV_VLC_BITS, 17, | |
84 | &ff_h261_mv_tab[0][1], 2, 1, | ||
85 | &ff_h261_mv_tab[0][0], 2, 1, 0); | ||
86 | 7 | VLC_INIT_STATIC_TABLE(h261_cbp_vlc, H261_CBP_VLC_BITS, 63, | |
87 | &ff_h261_cbp_tab[0][1], 2, 1, | ||
88 | &ff_h261_cbp_tab[0][0], 2, 1, 0); | ||
89 | 7 | INIT_FIRST_VLC_RL(ff_h261_rl_tcoeff, 552); | |
90 | 7 | } | |
91 | |||
92 | 13 | static av_cold int h261_decode_init(AVCodecContext *avctx) | |
93 | { | ||
94 | static AVOnce init_static_once = AV_ONCE_INIT; | ||
95 | 13 | H261DecContext *const h = avctx->priv_data; | |
96 | 13 | MpegEncContext *const s = &h->s; | |
97 | int ret; | ||
98 | |||
99 | 13 | avctx->framerate = (AVRational) { 30000, 1001 }; | |
100 | |||
101 | /* The H.261 analog of intra/key frames is setting the freeze picture release flag, | ||
102 | * but this does not guarantee that the frame uses intra-only encoding, | ||
103 | * so we still need to allocate dummy frames. So set pict_type to P here | ||
104 | * for all frames and override it after having decoded the frame. */ | ||
105 | 13 | s->pict_type = AV_PICTURE_TYPE_P; | |
106 | |||
107 | 13 | s->private_ctx = &h->common; | |
108 | // set defaults | ||
109 | 13 | ret = ff_mpv_decode_init(s, avctx); | |
110 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 13 times.
|
13 | if (ret < 0) |
111 | ✗ | return ret; | |
112 | |||
113 | 13 | s->out_format = FMT_H261; | |
114 | 13 | s->low_delay = 1; | |
115 | 13 | avctx->pix_fmt = AV_PIX_FMT_YUV420P; | |
116 | |||
117 | 13 | ff_thread_once(&init_static_once, h261_decode_init_static); | |
118 | |||
119 | 13 | return 0; | |
120 | } | ||
121 | |||
122 | 118800 | static inline void h261_init_dest(MpegEncContext *s) | |
123 | { | ||
124 | 118800 | const unsigned block_size = 8 >> s->avctx->lowres; | |
125 | 118800 | ff_init_block_index(s); | |
126 | 118800 | s->dest[0] += 2 * block_size; | |
127 | 118800 | s->dest[1] += block_size; | |
128 | 118800 | s->dest[2] += block_size; | |
129 | 118800 | } | |
130 | |||
131 | /** | ||
132 | * Decode the group of blocks header or slice header. | ||
133 | * @return <0 if an error occurred | ||
134 | */ | ||
135 | 3600 | static int h261_decode_gob_header(H261DecContext *h) | |
136 | { | ||
137 | unsigned int val; | ||
138 | 3600 | MpegEncContext *const s = &h->s; | |
139 | |||
140 |
2/2✓ Branch 0 taken 300 times.
✓ Branch 1 taken 3300 times.
|
3600 | if (!h->gob_start_code_skipped) { |
141 | /* Check for GOB Start Code */ | ||
142 | 300 | val = show_bits(&h->gb, 15); | |
143 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 300 times.
|
300 | if (val) |
144 | ✗ | return -1; | |
145 | |||
146 | /* We have a GBSC */ | ||
147 | 300 | skip_bits(&h->gb, 16); | |
148 | } | ||
149 | |||
150 | 3600 | h->gob_start_code_skipped = 0; | |
151 | |||
152 | 3600 | h->gob_number = get_bits(&h->gb, 4); /* GN */ | |
153 | 3600 | s->qscale = get_bits(&h->gb, 5); /* GQUANT */ | |
154 | |||
155 | /* Check if gob_number is valid */ | ||
156 |
1/2✓ Branch 0 taken 3600 times.
✗ Branch 1 not taken.
|
3600 | if (s->mb_height == 18) { // CIF |
157 |
2/4✓ Branch 0 taken 3600 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 3600 times.
|
3600 | if ((h->gob_number <= 0) || (h->gob_number > 12)) |
158 | ✗ | return -1; | |
159 | } else { // QCIF | ||
160 | ✗ | if ((h->gob_number != 1) && (h->gob_number != 3) && | |
161 | ✗ | (h->gob_number != 5)) | |
162 | ✗ | return -1; | |
163 | } | ||
164 | |||
165 | /* GEI */ | ||
166 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 3600 times.
|
3600 | if (skip_1stop_8data_bits(&h->gb) < 0) |
167 | ✗ | return AVERROR_INVALIDDATA; | |
168 | |||
169 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 3600 times.
|
3600 | if (s->qscale == 0) { |
170 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "qscale has forbidden 0 value\n"); | |
171 | ✗ | if (s->avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT)) | |
172 | ✗ | return -1; | |
173 | ✗ | s->qscale = 1; | |
174 | } | ||
175 | |||
176 | /* For the first transmitted macroblock in a GOB, MBA is the absolute | ||
177 | * address. For subsequent macroblocks, MBA is the difference between | ||
178 | * the absolute addresses of the macroblock and the last transmitted | ||
179 | * macroblock. */ | ||
180 | 3600 | h->current_mba = 0; | |
181 | 3600 | h->mba_diff = 0; | |
182 | |||
183 | 3600 | return 0; | |
184 | } | ||
185 | |||
186 | /** | ||
187 | * Decode skipped macroblocks. | ||
188 | * @return 0 | ||
189 | */ | ||
190 | 121541 | static int h261_decode_mb_skipped(H261DecContext *h, int mba1, int mba2) | |
191 | { | ||
192 | 121541 | MpegEncContext *const s = &h->s; | |
193 | int i; | ||
194 | |||
195 | 121541 | s->mb_intra = 0; | |
196 | |||
197 |
2/2✓ Branch 0 taken 859 times.
✓ Branch 1 taken 121541 times.
|
122400 | for (i = mba1; i < mba2; i++) { |
198 | int j, xy; | ||
199 | |||
200 | 859 | s->mb_x = ((h->gob_number - 1) % 2) * 11 + i % 11; | |
201 | 859 | s->mb_y = ((h->gob_number - 1) / 2) * 3 + i / 11; | |
202 | 859 | xy = s->mb_x + s->mb_y * s->mb_stride; | |
203 | 859 | h261_init_dest(s); | |
204 | |||
205 |
2/2✓ Branch 0 taken 5154 times.
✓ Branch 1 taken 859 times.
|
6013 | for (j = 0; j < 6; j++) |
206 | 5154 | s->block_last_index[j] = -1; | |
207 | |||
208 | 859 | s->mv_dir = MV_DIR_FORWARD; | |
209 | 859 | s->mv_type = MV_TYPE_16X16; | |
210 | 859 | s->cur_pic.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_FORWARD_MV; | |
211 | 859 | s->mv[0][0][0] = 0; | |
212 | 859 | s->mv[0][0][1] = 0; | |
213 | 859 | s->mb_skipped = 1; | |
214 | 859 | h->common.mtype &= ~MB_TYPE_H261_FIL; | |
215 | |||
216 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 859 times.
|
859 | if (s->cur_pic.motion_val[0]) { |
217 | ✗ | int b_stride = 2*s->mb_width + 1; | |
218 | ✗ | int b_xy = 2 * s->mb_x + (2 * s->mb_y) * b_stride; | |
219 | ✗ | s->cur_pic.motion_val[0][b_xy][0] = s->mv[0][0][0]; | |
220 | ✗ | s->cur_pic.motion_val[0][b_xy][1] = s->mv[0][0][1]; | |
221 | } | ||
222 | |||
223 | 859 | ff_mpv_reconstruct_mb(s, h->block); | |
224 | } | ||
225 | |||
226 | 121541 | return 0; | |
227 | } | ||
228 | |||
229 | 198948 | static int decode_mv_component(GetBitContext *gb, int v) | |
230 | { | ||
231 | 198948 | int mv_diff = get_vlc2(gb, h261_mv_vlc, H261_MV_VLC_BITS, 2); | |
232 | |||
233 | /* check if mv_diff is valid */ | ||
234 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 198948 times.
|
198948 | if (mv_diff < 0) |
235 | ✗ | return v; | |
236 | |||
237 |
4/4✓ Branch 0 taken 83960 times.
✓ Branch 1 taken 114988 times.
✓ Branch 3 taken 45885 times.
✓ Branch 4 taken 38075 times.
|
198948 | if (mv_diff && get_bits1(gb)) |
238 | 45885 | mv_diff = -mv_diff; | |
239 | |||
240 | 198948 | v += mv_diff; | |
241 |
2/2✓ Branch 0 taken 32 times.
✓ Branch 1 taken 198916 times.
|
198948 | if (v <= -16) |
242 | 32 | v += 32; | |
243 |
2/2✓ Branch 0 taken 35 times.
✓ Branch 1 taken 198881 times.
|
198916 | else if (v >= 16) |
244 | 35 | v -= 32; | |
245 | |||
246 | 198948 | return v; | |
247 | } | ||
248 | |||
249 | /** | ||
250 | * Decode a macroblock. | ||
251 | * @return <0 if an error occurred | ||
252 | */ | ||
253 | 591000 | static int h261_decode_block(H261DecContext *h, int16_t *block, int n, int coded) | |
254 | { | ||
255 | 591000 | MpegEncContext *const s = &h->s; | |
256 | int level, i, j, run; | ||
257 | 591000 | const RLTable *rl = &ff_h261_rl_tcoeff; | |
258 | const uint8_t *scan_table; | ||
259 | 591000 | const int qmul = s->qscale << 1, qadd = (s->qscale - 1) | 1; | |
260 | |||
261 | /* For the variable length encoding there are two code tables, one being | ||
262 | * used for the first transmitted LEVEL in INTER, INTER + MC and | ||
263 | * INTER + MC + FIL blocks, the second for all other LEVELs except the | ||
264 | * first one in INTRA blocks which is fixed length coded with 8 bits. | ||
265 | * NOTE: The two code tables only differ in one VLC so we handle that | ||
266 | * manually. */ | ||
267 | 591000 | scan_table = s->intra_scantable.permutated; | |
268 |
2/2✓ Branch 0 taken 101472 times.
✓ Branch 1 taken 489528 times.
|
591000 | if (s->mb_intra) { |
269 | /* DC coef */ | ||
270 | 101472 | level = get_bits(&h->gb, 8); | |
271 | // 0 (00000000b) and -128 (10000000b) are FORBIDDEN | ||
272 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 101472 times.
|
101472 | if ((level & 0x7F) == 0) { |
273 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", | |
274 | level, s->mb_x, s->mb_y); | ||
275 | ✗ | return -1; | |
276 | } | ||
277 | /* The code 1000 0000 is not used, the reconstruction level of 1024 | ||
278 | * being coded as 1111 1111. */ | ||
279 |
2/2✓ Branch 0 taken 1145 times.
✓ Branch 1 taken 100327 times.
|
101472 | if (level == 255) |
280 | 1145 | level = 128; | |
281 | 101472 | block[0] = level * 8; | |
282 | 101472 | i = 1; | |
283 |
2/2✓ Branch 0 taken 259485 times.
✓ Branch 1 taken 230043 times.
|
489528 | } else if (coded) { |
284 | // Run Level Code | ||
285 | // EOB Not possible for first level when cbp is available (that's why the table is different) | ||
286 | // 0 1 1s | ||
287 | // * * 0* | ||
288 | 259485 | int check = show_bits(&h->gb, 2); | |
289 | 259485 | i = 0; | |
290 |
2/2✓ Branch 0 taken 87589 times.
✓ Branch 1 taken 171896 times.
|
259485 | if (check & 0x2) { |
291 | 87589 | skip_bits(&h->gb, 2); | |
292 | 87589 | block[0] = qmul + qadd; | |
293 |
2/2✓ Branch 0 taken 45233 times.
✓ Branch 1 taken 42356 times.
|
87589 | block[0] *= (check & 0x1) ? -1 : 1; |
294 | 87589 | i = 1; | |
295 | } | ||
296 | } else { | ||
297 | 230043 | i = 0; | |
298 | } | ||
299 |
2/2✓ Branch 0 taken 230043 times.
✓ Branch 1 taken 360957 times.
|
591000 | if (!coded) { |
300 | 230043 | s->block_last_index[n] = i - 1; | |
301 | 230043 | return 0; | |
302 | } | ||
303 | { | ||
304 | 360957 | OPEN_READER(re, &h->gb); | |
305 | 360957 | i--; // offset by -1 to allow direct indexing of scan_table | |
306 | for (;;) { | ||
307 | 5175539 | UPDATE_CACHE(re, &h->gb); | |
308 |
2/2✓ Branch 1 taken 178749 times.
✓ Branch 2 taken 2589499 times.
|
2768248 | GET_RL_VLC(level, run, re, &h->gb, rl->rl_vlc[0], TCOEFF_VLC_BITS, 2, 0); |
309 |
2/2✓ Branch 0 taken 40537 times.
✓ Branch 1 taken 2727711 times.
|
2768248 | if (run == 66) { |
310 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 40537 times.
|
40537 | if (level) { |
311 | ✗ | CLOSE_READER(re, &h->gb); | |
312 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", | |
313 | s->mb_x, s->mb_y); | ||
314 | ✗ | return -1; | |
315 | } | ||
316 | /* escape */ | ||
317 | /* The remaining combinations of (run, level) are encoded with a | ||
318 | * 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits | ||
319 | * level. */ | ||
320 | 40537 | run = SHOW_UBITS(re, &h->gb, 6) + 1; | |
321 | 40537 | SKIP_CACHE(re, &h->gb, 6); | |
322 | 40537 | level = SHOW_SBITS(re, &h->gb, 8); | |
323 |
2/2✓ Branch 0 taken 21553 times.
✓ Branch 1 taken 18984 times.
|
40537 | if (level > 0) |
324 | 21553 | level = level * qmul + qadd; | |
325 |
1/2✓ Branch 0 taken 18984 times.
✗ Branch 1 not taken.
|
18984 | else if (level < 0) |
326 | 18984 | level = level * qmul - qadd; | |
327 | 40537 | SKIP_COUNTER(re, &h->gb, 6 + 8); | |
328 |
2/2✓ Branch 0 taken 360957 times.
✓ Branch 1 taken 2366754 times.
|
2727711 | } else if (level == 0) { |
329 | 360957 | break; | |
330 | } else { | ||
331 | 2366754 | level = level * qmul + qadd; | |
332 |
2/2✓ Branch 1 taken 1184977 times.
✓ Branch 2 taken 1181777 times.
|
2366754 | if (SHOW_UBITS(re, &h->gb, 1)) |
333 | 1184977 | level = -level; | |
334 | 2366754 | SKIP_COUNTER(re, &h->gb, 1); | |
335 | } | ||
336 | 2407291 | i += run; | |
337 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 2407291 times.
|
2407291 | if (i >= 64) { |
338 | ✗ | CLOSE_READER(re, &h->gb); | |
339 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n", | |
340 | s->mb_x, s->mb_y); | ||
341 | ✗ | return -1; | |
342 | } | ||
343 | 2407291 | j = scan_table[i]; | |
344 | 2407291 | block[j] = level; | |
345 | } | ||
346 | 360957 | CLOSE_READER(re, &h->gb); | |
347 | } | ||
348 | 360957 | s->block_last_index[n] = i; | |
349 | 360957 | return 0; | |
350 | } | ||
351 | |||
352 | 121541 | static int h261_decode_mb(H261DecContext *h) | |
353 | { | ||
354 | 121541 | MpegEncContext *const s = &h->s; | |
355 | 121541 | H261Context *const com = &h->common; | |
356 | int i, cbp, xy; | ||
357 | |||
358 | 121541 | cbp = 63; | |
359 | // Read mba | ||
360 | do { | ||
361 | 121541 | h->mba_diff = get_vlc2(&h->gb, h261_mba_vlc, | |
362 | H261_MBA_VLC_BITS, 2); | ||
363 | |||
364 | /* Check for slice end */ | ||
365 | /* NOTE: GOB can be empty (no MB data) or exist only of MBA_stuffing */ | ||
366 |
2/2✓ Branch 0 taken 3300 times.
✓ Branch 1 taken 118241 times.
|
121541 | if (h->mba_diff == MBA_STARTCODE) { // start code |
367 | 3300 | h->gob_start_code_skipped = 1; | |
368 | 3300 | return SLICE_END; | |
369 | } | ||
370 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 118241 times.
|
118241 | } while (h->mba_diff == MBA_STUFFING); // stuffing |
371 | |||
372 |
2/2✓ Branch 0 taken 300 times.
✓ Branch 1 taken 117941 times.
|
118241 | if (h->mba_diff < 0) { |
373 |
1/2✓ Branch 1 taken 300 times.
✗ Branch 2 not taken.
|
300 | if (get_bits_left(&h->gb) <= 7) |
374 | 300 | return SLICE_END; | |
375 | |||
376 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "illegal mba at %d %d\n", s->mb_x, s->mb_y); | |
377 | ✗ | return SLICE_ERROR; | |
378 | } | ||
379 | |||
380 | 117941 | h->mba_diff += 1; | |
381 | 117941 | h->current_mba += h->mba_diff; | |
382 | |||
383 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 117941 times.
|
117941 | if (h->current_mba > MBA_STUFFING) |
384 | ✗ | return SLICE_ERROR; | |
385 | |||
386 | 117941 | s->mb_x = ((h->gob_number - 1) % 2) * 11 + ((h->current_mba - 1) % 11); | |
387 | 117941 | s->mb_y = ((h->gob_number - 1) / 2) * 3 + ((h->current_mba - 1) / 11); | |
388 | 117941 | xy = s->mb_x + s->mb_y * s->mb_stride; | |
389 | 117941 | h261_init_dest(s); | |
390 | |||
391 | // Read mtype | ||
392 | 117941 | com->mtype = get_vlc2(&h->gb, h261_mtype_vlc, H261_MTYPE_VLC_BITS, 2); | |
393 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 117941 times.
|
117941 | if (com->mtype < 0) { |
394 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "Invalid mtype index\n"); | |
395 | ✗ | return SLICE_ERROR; | |
396 | } | ||
397 | |||
398 | // Read mquant | ||
399 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 117941 times.
|
117941 | if (IS_QUANT(com->mtype)) { |
400 | ✗ | s->qscale = get_bits(&h->gb, 5); | |
401 | ✗ | if (!s->qscale) | |
402 | ✗ | s->qscale = 1; | |
403 | } | ||
404 | |||
405 | 117941 | s->mb_intra = IS_INTRA4x4(com->mtype); | |
406 | |||
407 | // Read mv | ||
408 |
2/2✓ Branch 0 taken 99474 times.
✓ Branch 1 taken 18467 times.
|
117941 | if (IS_16X16(com->mtype)) { |
409 | /* Motion vector data is included for all MC macroblocks. MVD is | ||
410 | * obtained from the macroblock vector by subtracting the vector | ||
411 | * of the preceding macroblock. For this calculation the vector | ||
412 | * of the preceding macroblock is regarded as zero in the | ||
413 | * following three situations: | ||
414 | * 1) evaluating MVD for macroblocks 1, 12 and 23; | ||
415 | * 2) evaluating MVD for macroblocks in which MBA does not represent a difference of 1; | ||
416 | * 3) MTYPE of the previous macroblock was not MC. */ | ||
417 |
4/4✓ Branch 0 taken 96664 times.
✓ Branch 1 taken 2810 times.
✓ Branch 2 taken 93760 times.
✓ Branch 3 taken 2904 times.
|
99474 | if ((h->current_mba == 1) || (h->current_mba == 12) || |
418 |
4/4✓ Branch 0 taken 90931 times.
✓ Branch 1 taken 2829 times.
✓ Branch 2 taken 632 times.
✓ Branch 3 taken 90299 times.
|
93760 | (h->current_mba == 23) || (h->mba_diff != 1)) { |
419 | 9175 | h->current_mv_x = 0; | |
420 | 9175 | h->current_mv_y = 0; | |
421 | } | ||
422 | |||
423 | 99474 | h->current_mv_x = decode_mv_component(&h->gb, h->current_mv_x); | |
424 | 99474 | h->current_mv_y = decode_mv_component(&h->gb, h->current_mv_y); | |
425 | } else { | ||
426 | 18467 | h->current_mv_x = 0; | |
427 | 18467 | h->current_mv_y = 0; | |
428 | } | ||
429 | |||
430 | // Read cbp | ||
431 |
2/2✓ Branch 0 taken 81588 times.
✓ Branch 1 taken 36353 times.
|
117941 | if (HAS_CBP(com->mtype)) |
432 | 81588 | cbp = get_vlc2(&h->gb, h261_cbp_vlc, H261_CBP_VLC_BITS, 1) + 1; | |
433 | |||
434 |
2/2✓ Branch 0 taken 16912 times.
✓ Branch 1 taken 101029 times.
|
117941 | if (s->mb_intra) { |
435 | 16912 | s->cur_pic.mb_type[xy] = MB_TYPE_INTRA; | |
436 | 16912 | goto intra; | |
437 | } | ||
438 | |||
439 | //set motion vectors | ||
440 | 101029 | s->mv_dir = MV_DIR_FORWARD; | |
441 | 101029 | s->mv_type = MV_TYPE_16X16; | |
442 | 101029 | s->cur_pic.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_FORWARD_MV; | |
443 | 101029 | s->mv[0][0][0] = h->current_mv_x * 2; // gets divided by 2 in motion compensation | |
444 | 101029 | s->mv[0][0][1] = h->current_mv_y * 2; | |
445 | |||
446 |
1/2✓ Branch 0 taken 101029 times.
✗ Branch 1 not taken.
|
101029 | if (s->cur_pic.motion_val[0]) { |
447 | ✗ | int b_stride = 2*s->mb_width + 1; | |
448 | ✗ | int b_xy = 2 * s->mb_x + (2 * s->mb_y) * b_stride; | |
449 | ✗ | s->cur_pic.motion_val[0][b_xy][0] = s->mv[0][0][0]; | |
450 | ✗ | s->cur_pic.motion_val[0][b_xy][1] = s->mv[0][0][1]; | |
451 | } | ||
452 | |||
453 | 101029 | intra: | |
454 | /* decode each block */ | ||
455 |
4/4✓ Branch 0 taken 101029 times.
✓ Branch 1 taken 16912 times.
✓ Branch 2 taken 81588 times.
✓ Branch 3 taken 19441 times.
|
117941 | if (s->mb_intra || HAS_CBP(com->mtype)) { |
456 | 98500 | s->bdsp.clear_blocks(h->block[0]); | |
457 |
2/2✓ Branch 0 taken 591000 times.
✓ Branch 1 taken 98500 times.
|
689500 | for (i = 0; i < 6; i++) { |
458 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 591000 times.
|
591000 | if (h261_decode_block(h, h->block[i], i, cbp & 32) < 0) |
459 | ✗ | return SLICE_ERROR; | |
460 | 591000 | cbp += cbp; | |
461 | } | ||
462 | } else { | ||
463 |
2/2✓ Branch 0 taken 116646 times.
✓ Branch 1 taken 19441 times.
|
136087 | for (i = 0; i < 6; i++) |
464 | 116646 | s->block_last_index[i] = -1; | |
465 | } | ||
466 | |||
467 | 117941 | ff_mpv_reconstruct_mb(s, h->block); | |
468 | |||
469 | 117941 | return SLICE_OK; | |
470 | } | ||
471 | |||
472 | /** | ||
473 | * Decode the H.261 picture header. | ||
474 | * @return <0 if no startcode found | ||
475 | */ | ||
476 | 300 | static int h261_decode_picture_header(H261DecContext *h, int *is_key) | |
477 | { | ||
478 | 300 | MpegEncContext *const s = &h->s; | |
479 | 300 | uint32_t startcode = 0; | |
480 | |||
481 |
1/2✓ Branch 1 taken 6000 times.
✗ Branch 2 not taken.
|
6000 | for (int i = get_bits_left(&h->gb); i > 24; i -= 1) { |
482 | 6000 | startcode = ((startcode << 1) | get_bits(&h->gb, 1)) & 0x000FFFFF; | |
483 | |||
484 |
2/2✓ Branch 0 taken 300 times.
✓ Branch 1 taken 5700 times.
|
6000 | if (startcode == 0x10) |
485 | 300 | break; | |
486 | } | ||
487 | |||
488 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 300 times.
|
300 | if (startcode != 0x10) { |
489 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n"); | |
490 | ✗ | return -1; | |
491 | } | ||
492 | |||
493 | /* temporal reference */ | ||
494 | 300 | skip_bits(&h->gb, 5); /* picture timestamp */ | |
495 | |||
496 | /* PTYPE starts here */ | ||
497 | 300 | skip_bits1(&h->gb); /* split screen off */ | |
498 | 300 | skip_bits1(&h->gb); /* camera off */ | |
499 | 300 | *is_key = get_bits1(&h->gb); /* freeze picture release off */ | |
500 | |||
501 | 300 | int format = get_bits1(&h->gb); | |
502 | |||
503 | // only 2 formats possible | ||
504 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 300 times.
|
300 | if (format == 0) { // QCIF |
505 | ✗ | s->width = 176; | |
506 | ✗ | s->height = 144; | |
507 | } else { // CIF | ||
508 | 300 | s->width = 352; | |
509 | 300 | s->height = 288; | |
510 | } | ||
511 | |||
512 | 300 | skip_bits1(&h->gb); /* still image mode off */ | |
513 | 300 | skip_bits1(&h->gb); /* Reserved */ | |
514 | |||
515 | /* PEI */ | ||
516 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 300 times.
|
300 | if (skip_1stop_8data_bits(&h->gb) < 0) |
517 | ✗ | return AVERROR_INVALIDDATA; | |
518 | |||
519 | 300 | h->gob_number = 0; | |
520 | 300 | return 0; | |
521 | } | ||
522 | |||
523 | 3600 | static int h261_decode_gob(H261DecContext *h) | |
524 | { | ||
525 | 3600 | MpegEncContext *const s = &h->s; | |
526 | |||
527 | /* decode mb's */ | ||
528 |
1/2✓ Branch 0 taken 121541 times.
✗ Branch 1 not taken.
|
121541 | while (h->current_mba <= MBA_STUFFING) { |
529 | int ret; | ||
530 | /* DCT & quantize */ | ||
531 | 121541 | ret = h261_decode_mb(h); | |
532 |
2/2✓ Branch 0 taken 3600 times.
✓ Branch 1 taken 117941 times.
|
121541 | if (ret < 0) { |
533 |
1/2✓ Branch 0 taken 3600 times.
✗ Branch 1 not taken.
|
3600 | if (ret == SLICE_END) { |
534 | 3600 | h261_decode_mb_skipped(h, h->current_mba, 33); | |
535 | 3600 | return 0; | |
536 | } | ||
537 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", | |
538 | ✗ | s->mb_x + s->mb_y * s->mb_stride); | |
539 | ✗ | return -1; | |
540 | } | ||
541 | |||
542 | 117941 | h261_decode_mb_skipped(h, | |
543 | 117941 | h->current_mba - h->mba_diff, | |
544 | 117941 | h->current_mba - 1); | |
545 | } | ||
546 | |||
547 | ✗ | return -1; | |
548 | } | ||
549 | |||
550 | 300 | static int h261_decode_frame(AVCodecContext *avctx, AVFrame *pict, | |
551 | int *got_frame, AVPacket *avpkt) | ||
552 | { | ||
553 | 300 | H261DecContext *const h = avctx->priv_data; | |
554 | 300 | const uint8_t *buf = avpkt->data; | |
555 | 300 | int buf_size = avpkt->size; | |
556 | 300 | MpegEncContext *s = &h->s; | |
557 | int ret, is_key; | ||
558 | |||
559 | ff_dlog(avctx, "*****frame %"PRId64" size=%d\n", avctx->frame_num, buf_size); | ||
560 | ff_dlog(avctx, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]); | ||
561 | |||
562 | 300 | h->gob_start_code_skipped = 0; | |
563 | |||
564 | 300 | init_get_bits(&h->gb, buf, buf_size * 8); | |
565 | |||
566 | 300 | ret = h261_decode_picture_header(h, &is_key); | |
567 | |||
568 | /* skip if the header was thrashed */ | ||
569 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 300 times.
|
300 | if (ret < 0) { |
570 | ✗ | av_log(s->avctx, AV_LOG_ERROR, "header damaged\n"); | |
571 | ✗ | return -1; | |
572 | } | ||
573 | |||
574 |
2/4✓ Branch 0 taken 300 times.
✗ Branch 1 not taken.
✗ Branch 2 not taken.
✓ Branch 3 taken 300 times.
|
300 | if (s->width != avctx->coded_width || s->height != avctx->coded_height) { |
575 | ✗ | ff_mpv_common_end(s); | |
576 | } | ||
577 | |||
578 |
2/2✓ Branch 0 taken 6 times.
✓ Branch 1 taken 294 times.
|
300 | if (!s->context_initialized) { |
579 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 6 times.
|
6 | if ((ret = ff_mpv_common_init(s)) < 0) |
580 | ✗ | return ret; | |
581 | |||
582 | 6 | ret = ff_set_dimensions(avctx, s->width, s->height); | |
583 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 6 times.
|
6 | if (ret < 0) |
584 | ✗ | return ret; | |
585 | } | ||
586 | |||
587 |
1/4✗ Branch 0 not taken.
✓ Branch 1 taken 300 times.
✗ Branch 2 not taken.
✗ Branch 3 not taken.
|
300 | if ((avctx->skip_frame >= AVDISCARD_NONINTRA && !is_key) || |
588 |
1/2✗ Branch 0 not taken.
✓ Branch 1 taken 300 times.
|
300 | avctx->skip_frame >= AVDISCARD_ALL) |
589 | ✗ | return buf_size; | |
590 | |||
591 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 300 times.
|
300 | if (ff_mpv_frame_start(s, avctx) < 0) |
592 | ✗ | return -1; | |
593 | |||
594 | 300 | ff_mpeg_er_frame_start(s); | |
595 | |||
596 | /* decode each macroblock */ | ||
597 | 300 | s->mb_x = 0; | |
598 | 300 | s->mb_y = 0; | |
599 | |||
600 |
3/4✓ Branch 0 taken 3900 times.
✗ Branch 1 not taken.
✓ Branch 2 taken 3600 times.
✓ Branch 3 taken 300 times.
|
3900 | while (h->gob_number < (s->mb_height == 18 ? 12 : 5)) { |
601 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 3600 times.
|
3600 | if (h261_decode_gob_header(h) < 0) |
602 | ✗ | break; | |
603 | 3600 | h261_decode_gob(h); | |
604 | } | ||
605 | 300 | ff_mpv_frame_end(s); | |
606 | |||
607 |
2/2✓ Branch 0 taken 30 times.
✓ Branch 1 taken 270 times.
|
300 | if (is_key) { |
608 | 30 | s->cur_pic.ptr->f->pict_type = AV_PICTURE_TYPE_I; | |
609 | 30 | s->cur_pic.ptr->f->flags |= AV_FRAME_FLAG_KEY; | |
610 | } | ||
611 | |||
612 |
1/2✗ Branch 1 not taken.
✓ Branch 2 taken 300 times.
|
300 | if ((ret = av_frame_ref(pict, s->cur_pic.ptr->f)) < 0) |
613 | ✗ | return ret; | |
614 | 300 | ff_print_debug_info(s, s->cur_pic.ptr, pict); | |
615 | |||
616 | 300 | *got_frame = 1; | |
617 | |||
618 | 300 | return buf_size; | |
619 | } | ||
620 | |||
621 | const FFCodec ff_h261_decoder = { | ||
622 | .p.name = "h261", | ||
623 | CODEC_LONG_NAME("H.261"), | ||
624 | .p.type = AVMEDIA_TYPE_VIDEO, | ||
625 | .p.id = AV_CODEC_ID_H261, | ||
626 | .priv_data_size = sizeof(H261DecContext), | ||
627 | .init = h261_decode_init, | ||
628 | FF_CODEC_DECODE_CB(h261_decode_frame), | ||
629 | .close = ff_mpv_decode_close, | ||
630 | .p.capabilities = AV_CODEC_CAP_DR1, | ||
631 | .p.max_lowres = 3, | ||
632 | .caps_internal = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM, | ||
633 | }; | ||
634 |