blob: b58c21be9382379c6d28d56aa7e08ff0f4e90453
1 | /* |
2 | * Microsoft Screen 4 (aka Microsoft Expression Encoder Screen) decoder |
3 | * Copyright (c) 2012 Konstantin Shishkov |
4 | * |
5 | * This file is part of FFmpeg. |
6 | * |
7 | * FFmpeg is free software; you can redistribute it and/or |
8 | * modify it under the terms of the GNU Lesser General Public |
9 | * License as published by the Free Software Foundation; either |
10 | * version 2.1 of the License, or (at your option) any later version. |
11 | * |
12 | * FFmpeg is distributed in the hope that it will be useful, |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 | * Lesser General Public License for more details. |
16 | * |
17 | * You should have received a copy of the GNU Lesser General Public |
18 | * License along with FFmpeg; if not, write to the Free Software |
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
20 | */ |
21 | |
22 | /** |
23 | * @file |
24 | * Microsoft Screen 4 (aka Microsoft Titanium Screen 2, |
25 | * aka Microsoft Expression Encoder Screen) decoder |
26 | */ |
27 | |
28 | #include "avcodec.h" |
29 | #include "bytestream.h" |
30 | #include "get_bits.h" |
31 | #include "internal.h" |
32 | #include "mss34dsp.h" |
33 | #include "unary.h" |
34 | |
35 | #define HEADER_SIZE 8 |
36 | |
37 | enum FrameType { |
38 | INTRA_FRAME = 0, |
39 | INTER_FRAME, |
40 | SKIP_FRAME |
41 | }; |
42 | |
43 | enum BlockType { |
44 | SKIP_BLOCK = 0, |
45 | DCT_BLOCK, |
46 | IMAGE_BLOCK, |
47 | }; |
48 | |
49 | enum CachePos { |
50 | LEFT = 0, |
51 | TOP_LEFT, |
52 | TOP, |
53 | }; |
54 | |
55 | static const uint8_t mss4_dc_vlc_lens[2][16] = { |
56 | { 0, 1, 5, 1, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0 }, |
57 | { 0, 3, 1, 1, 1, 1, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0 } |
58 | }; |
59 | |
60 | static const uint8_t mss4_ac_vlc_lens[2][16] = { |
61 | { 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 125 }, |
62 | { 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 119 } |
63 | }; |
64 | |
65 | static const uint8_t mss4_ac_vlc_syms[2][162] = { |
66 | { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, |
67 | 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, |
68 | 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xA1, 0x08, |
69 | 0x23, 0x42, 0xB1, 0xC1, 0x15, 0x52, 0xD1, 0xF0, |
70 | 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0A, 0x16, |
71 | 0x17, 0x18, 0x19, 0x1A, 0x25, 0x26, 0x27, 0x28, |
72 | 0x29, 0x2A, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, |
73 | 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, |
74 | 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, |
75 | 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, |
76 | 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, |
77 | 0x7A, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, |
78 | 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, |
79 | 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, |
80 | 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, |
81 | 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, 0xC4, 0xC5, |
82 | 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, 0xD3, 0xD4, |
83 | 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xE1, 0xE2, |
84 | 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, |
85 | 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, |
86 | 0xF9, 0xFA }, |
87 | { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, |
88 | 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, |
89 | 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, |
90 | 0xA1, 0xB1, 0xC1, 0x09, 0x23, 0x33, 0x52, 0xF0, |
91 | 0x15, 0x62, 0x72, 0xD1, 0x0A, 0x16, 0x24, 0x34, |
92 | 0xE1, 0x25, 0xF1, 0x17, 0x18, 0x19, 0x1A, 0x26, |
93 | 0x27, 0x28, 0x29, 0x2A, 0x35, 0x36, 0x37, 0x38, |
94 | 0x39, 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, |
95 | 0x49, 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, |
96 | 0x59, 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, |
97 | 0x69, 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, |
98 | 0x79, 0x7A, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, |
99 | 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, |
100 | 0x97, 0x98, 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, |
101 | 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4, |
102 | 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, |
103 | 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, |
104 | 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, |
105 | 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, |
106 | 0xEA, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, |
107 | 0xF9, 0xFA } |
108 | }; |
109 | |
110 | static const uint8_t vec_len_syms[2][4] = { |
111 | { 4, 2, 3, 1 }, |
112 | { 4, 1, 2, 3 } |
113 | }; |
114 | |
115 | static const uint8_t mss4_vec_entry_vlc_lens[2][16] = { |
116 | { 0, 2, 2, 3, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, |
117 | { 0, 1, 5, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } |
118 | }; |
119 | |
120 | static const uint8_t mss4_vec_entry_vlc_syms[2][9] = { |
121 | { 0, 7, 6, 5, 8, 4, 3, 1, 2 }, |
122 | { 0, 2, 3, 4, 5, 6, 7, 1, 8 } |
123 | }; |
124 | |
125 | #define MAX_ENTRIES 162 |
126 | |
127 | typedef struct MSS4Context { |
128 | AVFrame *pic; |
129 | |
130 | VLC dc_vlc[2], ac_vlc[2]; |
131 | VLC vec_entry_vlc[2]; |
132 | int block[64]; |
133 | uint8_t imgbuf[3][16 * 16]; |
134 | |
135 | int quality; |
136 | uint16_t quant_mat[2][64]; |
137 | |
138 | int *prev_dc[3]; |
139 | ptrdiff_t dc_stride[3]; |
140 | int dc_cache[4][4]; |
141 | |
142 | int prev_vec[3][4]; |
143 | } MSS4Context; |
144 | |
145 | static av_cold int mss4_init_vlc(VLC *vlc, const uint8_t *lens, |
146 | const uint8_t *syms, int num_syms) |
147 | { |
148 | uint8_t bits[MAX_ENTRIES]; |
149 | uint16_t codes[MAX_ENTRIES]; |
150 | int i, j; |
151 | int prefix = 0, max_bits = 0, idx = 0; |
152 | |
153 | for (i = 0; i < 16; i++) { |
154 | for (j = 0; j < lens[i]; j++) { |
155 | bits[idx] = i + 1; |
156 | codes[idx] = prefix++; |
157 | max_bits = i + 1; |
158 | idx++; |
159 | } |
160 | prefix <<= 1; |
161 | } |
162 | |
163 | return ff_init_vlc_sparse(vlc, FFMIN(max_bits, 9), num_syms, bits, 1, 1, |
164 | codes, 2, 2, syms, 1, 1, 0); |
165 | } |
166 | |
167 | static av_cold int mss4_init_vlcs(MSS4Context *ctx) |
168 | { |
169 | int ret, i; |
170 | |
171 | for (i = 0; i < 2; i++) { |
172 | ret = mss4_init_vlc(&ctx->dc_vlc[i], mss4_dc_vlc_lens[i], NULL, 12); |
173 | if (ret) |
174 | return ret; |
175 | ret = mss4_init_vlc(&ctx->ac_vlc[i], mss4_ac_vlc_lens[i], |
176 | mss4_ac_vlc_syms[i], 162); |
177 | if (ret) |
178 | return ret; |
179 | ret = mss4_init_vlc(&ctx->vec_entry_vlc[i], mss4_vec_entry_vlc_lens[i], |
180 | mss4_vec_entry_vlc_syms[i], 9); |
181 | if (ret) |
182 | return ret; |
183 | } |
184 | return 0; |
185 | } |
186 | |
187 | static av_cold void mss4_free_vlcs(MSS4Context *ctx) |
188 | { |
189 | int i; |
190 | |
191 | for (i = 0; i < 2; i++) { |
192 | ff_free_vlc(&ctx->dc_vlc[i]); |
193 | ff_free_vlc(&ctx->ac_vlc[i]); |
194 | ff_free_vlc(&ctx->vec_entry_vlc[i]); |
195 | } |
196 | } |
197 | |
198 | /* This function returns values in the range |
199 | * (-range + 1; -range/2] U [range/2; range - 1) |
200 | * i.e. |
201 | * nbits = 0 -> 0 |
202 | * nbits = 1 -> -1, 1 |
203 | * nbits = 2 -> -3, -2, 2, 3 |
204 | */ |
205 | static av_always_inline int get_coeff_bits(GetBitContext *gb, int nbits) |
206 | { |
207 | int val; |
208 | |
209 | if (!nbits) |
210 | return 0; |
211 | |
212 | val = get_bits(gb, nbits); |
213 | if (val < (1 << (nbits - 1))) |
214 | val -= (1 << nbits) - 1; |
215 | |
216 | return val; |
217 | } |
218 | |
219 | static inline int get_coeff(GetBitContext *gb, VLC *vlc) |
220 | { |
221 | int val = get_vlc2(gb, vlc->table, vlc->bits, 2); |
222 | |
223 | return get_coeff_bits(gb, val); |
224 | } |
225 | |
226 | static int mss4_decode_dct(GetBitContext *gb, VLC *dc_vlc, VLC *ac_vlc, |
227 | int *block, int *dc_cache, |
228 | int bx, int by, uint16_t *quant_mat) |
229 | { |
230 | int skip, val, pos = 1, zz_pos, dc; |
231 | |
232 | memset(block, 0, sizeof(*block) * 64); |
233 | |
234 | dc = get_coeff(gb, dc_vlc); |
235 | // DC prediction is the same as in MSS3 |
236 | if (by) { |
237 | if (bx) { |
238 | int l, tl, t; |
239 | |
240 | l = dc_cache[LEFT]; |
241 | tl = dc_cache[TOP_LEFT]; |
242 | t = dc_cache[TOP]; |
243 | |
244 | if (FFABS(t - tl) <= FFABS(l - tl)) |
245 | dc += l; |
246 | else |
247 | dc += t; |
248 | } else { |
249 | dc += dc_cache[TOP]; |
250 | } |
251 | } else if (bx) { |
252 | dc += dc_cache[LEFT]; |
253 | } |
254 | dc_cache[LEFT] = dc; |
255 | block[0] = dc * quant_mat[0]; |
256 | |
257 | while (pos < 64) { |
258 | val = get_vlc2(gb, ac_vlc->table, 9, 2); |
259 | if (!val) |
260 | return 0; |
261 | if (val == -1) |
262 | return -1; |
263 | if (val == 0xF0) { |
264 | pos += 16; |
265 | continue; |
266 | } |
267 | skip = val >> 4; |
268 | val = get_coeff_bits(gb, val & 0xF); |
269 | pos += skip; |
270 | if (pos >= 64) |
271 | return -1; |
272 | |
273 | zz_pos = ff_zigzag_direct[pos]; |
274 | block[zz_pos] = val * quant_mat[zz_pos]; |
275 | pos++; |
276 | } |
277 | |
278 | return pos == 64 ? 0 : -1; |
279 | } |
280 | |
281 | static int mss4_decode_dct_block(MSS4Context *c, GetBitContext *gb, |
282 | uint8_t *dst[3], int mb_x, int mb_y) |
283 | { |
284 | int i, j, k, ret; |
285 | uint8_t *out = dst[0]; |
286 | |
287 | for (j = 0; j < 2; j++) { |
288 | for (i = 0; i < 2; i++) { |
289 | int xpos = mb_x * 2 + i; |
290 | c->dc_cache[j][TOP_LEFT] = c->dc_cache[j][TOP]; |
291 | c->dc_cache[j][TOP] = c->prev_dc[0][mb_x * 2 + i]; |
292 | ret = mss4_decode_dct(gb, c->dc_vlc, c->ac_vlc, c->block, |
293 | c->dc_cache[j], |
294 | xpos, mb_y * 2 + j, c->quant_mat[0]); |
295 | if (ret) |
296 | return ret; |
297 | c->prev_dc[0][mb_x * 2 + i] = c->dc_cache[j][LEFT]; |
298 | |
299 | ff_mss34_dct_put(out + xpos * 8, c->pic->linesize[0], |
300 | c->block); |
301 | } |
302 | out += 8 * c->pic->linesize[0]; |
303 | } |
304 | |
305 | for (i = 1; i < 3; i++) { |
306 | c->dc_cache[i + 1][TOP_LEFT] = c->dc_cache[i + 1][TOP]; |
307 | c->dc_cache[i + 1][TOP] = c->prev_dc[i][mb_x]; |
308 | ret = mss4_decode_dct(gb, c->dc_vlc + 1, c->ac_vlc + 1, |
309 | c->block, c->dc_cache[i + 1], mb_x, mb_y, |
310 | c->quant_mat[1]); |
311 | if (ret) |
312 | return ret; |
313 | c->prev_dc[i][mb_x] = c->dc_cache[i + 1][LEFT]; |
314 | |
315 | ff_mss34_dct_put(c->imgbuf[i], 8, c->block); |
316 | out = dst[i] + mb_x * 16; |
317 | // Since the DCT block is coded as YUV420 and the whole frame as YUV444, |
318 | // we need to scale chroma. |
319 | for (j = 0; j < 16; j++) { |
320 | for (k = 0; k < 8; k++) |
321 | AV_WN16A(out + k * 2, c->imgbuf[i][k + (j & ~1) * 4] * 0x101); |
322 | out += c->pic->linesize[i]; |
323 | } |
324 | } |
325 | |
326 | return 0; |
327 | } |
328 | |
329 | static void read_vec_pos(GetBitContext *gb, int *vec_pos, int *sel_flag, |
330 | int *sel_len, int *prev) |
331 | { |
332 | int i, y_flag = 0; |
333 | |
334 | for (i = 2; i >= 0; i--) { |
335 | if (!sel_flag[i]) { |
336 | vec_pos[i] = 0; |
337 | continue; |
338 | } |
339 | if ((!i && !y_flag) || get_bits1(gb)) { |
340 | if (sel_len[i] > 0) { |
341 | int pval = prev[i]; |
342 | vec_pos[i] = get_bits(gb, sel_len[i]); |
343 | if (vec_pos[i] >= pval) |
344 | vec_pos[i]++; |
345 | } else { |
346 | vec_pos[i] = !prev[i]; |
347 | } |
348 | y_flag = 1; |
349 | } else { |
350 | vec_pos[i] = prev[i]; |
351 | } |
352 | } |
353 | } |
354 | |
355 | static int get_value_cached(GetBitContext *gb, int vec_pos, uint8_t *vec, |
356 | int vec_size, int component, int shift, int *prev) |
357 | { |
358 | if (vec_pos < vec_size) |
359 | return vec[vec_pos]; |
360 | if (!get_bits1(gb)) |
361 | return prev[component]; |
362 | prev[component] = get_bits(gb, 8 - shift) << shift; |
363 | return prev[component]; |
364 | } |
365 | |
366 | #define MKVAL(vals) ((vals)[0] | ((vals)[1] << 3) | ((vals)[2] << 6)) |
367 | |
368 | /* Image mode - the hardest to comprehend MSS4 coding mode. |
369 | * |
370 | * In this mode all three 16x16 blocks are coded together with a method |
371 | * remotely similar to the methods employed in MSS1-MSS3. |
372 | * The idea is that every component has a vector of 1-4 most common symbols |
373 | * and an escape mode for reading new value from the bitstream. Decoding |
374 | * consists of retrieving pixel values from the vector or reading new ones |
375 | * from the bitstream; depending on flags read from the bitstream, these vector |
376 | * positions can be updated or reused from the state of the previous line |
377 | * or previous pixel. |
378 | */ |
379 | static int mss4_decode_image_block(MSS4Context *ctx, GetBitContext *gb, |
380 | uint8_t *picdst[3], int mb_x, int mb_y) |
381 | { |
382 | uint8_t vec[3][4]; |
383 | int vec_len[3]; |
384 | int sel_len[3], sel_flag[3]; |
385 | int i, j, k, mode, split; |
386 | int prev_vec1 = 0, prev_split = 0; |
387 | int vals[3] = { 0 }; |
388 | int prev_pix[3] = { 0 }; |
389 | int prev_mode[16] = { 0 }; |
390 | uint8_t *dst[3]; |
391 | |
392 | const int val_shift = ctx->quality == 100 ? 0 : 2; |
393 | |
394 | for (i = 0; i < 3; i++) |
395 | dst[i] = ctx->imgbuf[i]; |
396 | |
397 | for (i = 0; i < 3; i++) { |
398 | vec_len[i] = vec_len_syms[!!i][get_unary(gb, 0, 3)]; |
399 | for (j = 0; j < vec_len[i]; j++) { |
400 | vec[i][j] = get_coeff(gb, &ctx->vec_entry_vlc[!!i]); |
401 | vec[i][j] += ctx->prev_vec[i][j]; |
402 | ctx->prev_vec[i][j] = vec[i][j]; |
403 | } |
404 | sel_flag[i] = vec_len[i] > 1; |
405 | sel_len[i] = vec_len[i] > 2 ? vec_len[i] - 2 : 0; |
406 | } |
407 | |
408 | for (j = 0; j < 16; j++) { |
409 | if (get_bits1(gb)) { |
410 | split = 0; |
411 | if (get_bits1(gb)) { |
412 | prev_mode[0] = 0; |
413 | vals[0] = vals[1] = vals[2] = 0; |
414 | mode = 2; |
415 | } else { |
416 | mode = get_bits1(gb); |
417 | if (mode) |
418 | split = get_bits(gb, 4); |
419 | } |
420 | for (i = 0; i < 16; i++) { |
421 | if (mode <= 1) { |
422 | vals[0] = prev_mode[i] & 7; |
423 | vals[1] = (prev_mode[i] >> 3) & 7; |
424 | vals[2] = prev_mode[i] >> 6; |
425 | if (mode == 1 && i == split) { |
426 | read_vec_pos(gb, vals, sel_flag, sel_len, vals); |
427 | } |
428 | } else if (mode == 2) { |
429 | if (get_bits1(gb)) |
430 | read_vec_pos(gb, vals, sel_flag, sel_len, vals); |
431 | } |
432 | for (k = 0; k < 3; k++) |
433 | *dst[k]++ = get_value_cached(gb, vals[k], vec[k], |
434 | vec_len[k], k, |
435 | val_shift, prev_pix); |
436 | prev_mode[i] = MKVAL(vals); |
437 | } |
438 | } else { |
439 | if (get_bits1(gb)) { |
440 | split = get_bits(gb, 4); |
441 | if (split >= prev_split) |
442 | split++; |
443 | prev_split = split; |
444 | } else { |
445 | split = prev_split; |
446 | } |
447 | if (split) { |
448 | vals[0] = prev_mode[0] & 7; |
449 | vals[1] = (prev_mode[0] >> 3) & 7; |
450 | vals[2] = prev_mode[0] >> 6; |
451 | for (i = 0; i < 3; i++) { |
452 | for (k = 0; k < split; k++) { |
453 | *dst[i]++ = get_value_cached(gb, vals[i], vec[i], |
454 | vec_len[i], i, val_shift, |
455 | prev_pix); |
456 | prev_mode[k] = MKVAL(vals); |
457 | } |
458 | } |
459 | } |
460 | |
461 | if (split != 16) { |
462 | vals[0] = prev_vec1 & 7; |
463 | vals[1] = (prev_vec1 >> 3) & 7; |
464 | vals[2] = prev_vec1 >> 6; |
465 | if (get_bits1(gb)) { |
466 | read_vec_pos(gb, vals, sel_flag, sel_len, vals); |
467 | prev_vec1 = MKVAL(vals); |
468 | } |
469 | for (i = 0; i < 3; i++) { |
470 | for (k = 0; k < 16 - split; k++) { |
471 | *dst[i]++ = get_value_cached(gb, vals[i], vec[i], |
472 | vec_len[i], i, val_shift, |
473 | prev_pix); |
474 | prev_mode[split + k] = MKVAL(vals); |
475 | } |
476 | } |
477 | } |
478 | } |
479 | } |
480 | |
481 | for (i = 0; i < 3; i++) |
482 | for (j = 0; j < 16; j++) |
483 | memcpy(picdst[i] + mb_x * 16 + j * ctx->pic->linesize[i], |
484 | ctx->imgbuf[i] + j * 16, 16); |
485 | |
486 | return 0; |
487 | } |
488 | |
489 | static inline void mss4_update_dc_cache(MSS4Context *c, int mb_x) |
490 | { |
491 | int i; |
492 | |
493 | c->dc_cache[0][TOP] = c->prev_dc[0][mb_x * 2 + 1]; |
494 | c->dc_cache[0][LEFT] = 0; |
495 | c->dc_cache[1][TOP] = 0; |
496 | c->dc_cache[1][LEFT] = 0; |
497 | |
498 | for (i = 0; i < 2; i++) |
499 | c->prev_dc[0][mb_x * 2 + i] = 0; |
500 | |
501 | for (i = 1; i < 3; i++) { |
502 | c->dc_cache[i + 1][TOP] = c->prev_dc[i][mb_x]; |
503 | c->dc_cache[i + 1][LEFT] = 0; |
504 | c->prev_dc[i][mb_x] = 0; |
505 | } |
506 | } |
507 | |
508 | static int mss4_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, |
509 | AVPacket *avpkt) |
510 | { |
511 | const uint8_t *buf = avpkt->data; |
512 | int buf_size = avpkt->size; |
513 | MSS4Context *c = avctx->priv_data; |
514 | GetBitContext gb; |
515 | GetByteContext bc; |
516 | uint8_t *dst[3]; |
517 | int width, height, quality, frame_type; |
518 | int x, y, i, mb_width, mb_height, blk_type; |
519 | int ret; |
520 | |
521 | if (buf_size < HEADER_SIZE) { |
522 | av_log(avctx, AV_LOG_ERROR, |
523 | "Frame should have at least %d bytes, got %d instead\n", |
524 | HEADER_SIZE, buf_size); |
525 | return AVERROR_INVALIDDATA; |
526 | } |
527 | |
528 | bytestream2_init(&bc, buf, buf_size); |
529 | width = bytestream2_get_be16(&bc); |
530 | height = bytestream2_get_be16(&bc); |
531 | bytestream2_skip(&bc, 2); |
532 | quality = bytestream2_get_byte(&bc); |
533 | frame_type = bytestream2_get_byte(&bc); |
534 | |
535 | if (width > avctx->width || |
536 | height != avctx->height) { |
537 | av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d\n", |
538 | width, height); |
539 | return AVERROR_INVALIDDATA; |
540 | } |
541 | if (quality < 1 || quality > 100) { |
542 | av_log(avctx, AV_LOG_ERROR, "Invalid quality setting %d\n", quality); |
543 | return AVERROR_INVALIDDATA; |
544 | } |
545 | if ((frame_type & ~3) || frame_type == 3) { |
546 | av_log(avctx, AV_LOG_ERROR, "Invalid frame type %d\n", frame_type); |
547 | return AVERROR_INVALIDDATA; |
548 | } |
549 | |
550 | if (frame_type != SKIP_FRAME && !bytestream2_get_bytes_left(&bc)) { |
551 | av_log(avctx, AV_LOG_ERROR, |
552 | "Empty frame found but it is not a skip frame.\n"); |
553 | return AVERROR_INVALIDDATA; |
554 | } |
555 | |
556 | if ((ret = ff_reget_buffer(avctx, c->pic)) < 0) |
557 | return ret; |
558 | c->pic->key_frame = (frame_type == INTRA_FRAME); |
559 | c->pic->pict_type = (frame_type == INTRA_FRAME) ? AV_PICTURE_TYPE_I |
560 | : AV_PICTURE_TYPE_P; |
561 | if (frame_type == SKIP_FRAME) { |
562 | *got_frame = 1; |
563 | if ((ret = av_frame_ref(data, c->pic)) < 0) |
564 | return ret; |
565 | |
566 | return buf_size; |
567 | } |
568 | |
569 | if (c->quality != quality) { |
570 | c->quality = quality; |
571 | for (i = 0; i < 2; i++) |
572 | ff_mss34_gen_quant_mat(c->quant_mat[i], quality, !i); |
573 | } |
574 | |
575 | if ((ret = init_get_bits8(&gb, buf + HEADER_SIZE, buf_size - HEADER_SIZE)) < 0) |
576 | return ret; |
577 | |
578 | mb_width = FFALIGN(width, 16) >> 4; |
579 | mb_height = FFALIGN(height, 16) >> 4; |
580 | dst[0] = c->pic->data[0]; |
581 | dst[1] = c->pic->data[1]; |
582 | dst[2] = c->pic->data[2]; |
583 | |
584 | memset(c->prev_vec, 0, sizeof(c->prev_vec)); |
585 | for (y = 0; y < mb_height; y++) { |
586 | memset(c->dc_cache, 0, sizeof(c->dc_cache)); |
587 | for (x = 0; x < mb_width; x++) { |
588 | blk_type = decode012(&gb); |
589 | switch (blk_type) { |
590 | case DCT_BLOCK: |
591 | if (mss4_decode_dct_block(c, &gb, dst, x, y) < 0) { |
592 | av_log(avctx, AV_LOG_ERROR, |
593 | "Error decoding DCT block %d,%d\n", |
594 | x, y); |
595 | return AVERROR_INVALIDDATA; |
596 | } |
597 | break; |
598 | case IMAGE_BLOCK: |
599 | if (mss4_decode_image_block(c, &gb, dst, x, y) < 0) { |
600 | av_log(avctx, AV_LOG_ERROR, |
601 | "Error decoding VQ block %d,%d\n", |
602 | x, y); |
603 | return AVERROR_INVALIDDATA; |
604 | } |
605 | break; |
606 | case SKIP_BLOCK: |
607 | if (frame_type == INTRA_FRAME) { |
608 | av_log(avctx, AV_LOG_ERROR, "Skip block in intra frame\n"); |
609 | return AVERROR_INVALIDDATA; |
610 | } |
611 | break; |
612 | } |
613 | if (blk_type != DCT_BLOCK) |
614 | mss4_update_dc_cache(c, x); |
615 | } |
616 | dst[0] += c->pic->linesize[0] * 16; |
617 | dst[1] += c->pic->linesize[1] * 16; |
618 | dst[2] += c->pic->linesize[2] * 16; |
619 | } |
620 | |
621 | if ((ret = av_frame_ref(data, c->pic)) < 0) |
622 | return ret; |
623 | |
624 | *got_frame = 1; |
625 | |
626 | return buf_size; |
627 | } |
628 | |
629 | static av_cold int mss4_decode_end(AVCodecContext *avctx) |
630 | { |
631 | MSS4Context * const c = avctx->priv_data; |
632 | int i; |
633 | |
634 | av_frame_free(&c->pic); |
635 | for (i = 0; i < 3; i++) |
636 | av_freep(&c->prev_dc[i]); |
637 | mss4_free_vlcs(c); |
638 | |
639 | return 0; |
640 | } |
641 | |
642 | static av_cold int mss4_decode_init(AVCodecContext *avctx) |
643 | { |
644 | MSS4Context * const c = avctx->priv_data; |
645 | int i; |
646 | |
647 | if (mss4_init_vlcs(c)) { |
648 | av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n"); |
649 | mss4_free_vlcs(c); |
650 | return AVERROR(ENOMEM); |
651 | } |
652 | for (i = 0; i < 3; i++) { |
653 | c->dc_stride[i] = FFALIGN(avctx->width, 16) >> (2 + !!i); |
654 | c->prev_dc[i] = av_malloc_array(c->dc_stride[i], sizeof(**c->prev_dc)); |
655 | if (!c->prev_dc[i]) { |
656 | av_log(avctx, AV_LOG_ERROR, "Cannot allocate buffer\n"); |
657 | mss4_free_vlcs(c); |
658 | return AVERROR(ENOMEM); |
659 | } |
660 | } |
661 | |
662 | c->pic = av_frame_alloc(); |
663 | if (!c->pic) { |
664 | mss4_decode_end(avctx); |
665 | return AVERROR(ENOMEM); |
666 | } |
667 | |
668 | avctx->pix_fmt = AV_PIX_FMT_YUV444P; |
669 | |
670 | return 0; |
671 | } |
672 | |
673 | AVCodec ff_mts2_decoder = { |
674 | .name = "mts2", |
675 | .long_name = NULL_IF_CONFIG_SMALL("MS Expression Encoder Screen"), |
676 | .type = AVMEDIA_TYPE_VIDEO, |
677 | .id = AV_CODEC_ID_MTS2, |
678 | .priv_data_size = sizeof(MSS4Context), |
679 | .init = mss4_decode_init, |
680 | .close = mss4_decode_end, |
681 | .decode = mss4_decode_frame, |
682 | .capabilities = AV_CODEC_CAP_DR1, |
683 | }; |
684 |