1 /*
2 * Copyright (C) 2005 Ole André Vadla Ravnås <oleavr@gmail.com>
3 * Copyright (C) 2008 Ramiro Polla
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 #include <stdlib.h>
23 #include <string.h>
24 #include <stdint.h>
25
26 #include "avcodec.h"
27 #include "blockdsp.h"
28 #include "internal.h"
29 #include "get_bits.h"
30 #include "bytestream.h"
31 #include "bswapdsp.h"
32 #include "hpeldsp.h"
33 #include "idctdsp.h"
34 #include "thread.h"
35
36 #define MIMIC_HEADER_SIZE 20
37
38 typedef struct MimicContext {
39 AVCodecContext *avctx;
40
41 int num_vblocks[3];
42 int num_hblocks[3];
43
44 void *swap_buf;
45 int swap_buf_size;
46
47 int cur_index;
48 int prev_index;
49
50 ThreadFrame frames [16];
51
52 DECLARE_ALIGNED(32, int16_t, dct_block)[64];
53
54 GetBitContext gb;
55 ScanTable scantable;
56 BlockDSPContext bdsp;
57 BswapDSPContext bbdsp;
58 HpelDSPContext hdsp;
59 IDCTDSPContext idsp;
60 VLC vlc;
61
62 /* Kept in the context so multithreading can have a constant to read from */
63 int next_cur_index;
64 int next_prev_index;
65 } MimicContext;
66
67 static const uint32_t huffcodes[] = {
68 0x0000000a, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
69 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
70 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x0000000b,
71 0x0000001b, 0x00000038, 0x00000078, 0x00000079, 0x0000007a, 0x000000f9,
72 0x000000fa, 0x000003fb, 0x000007f8, 0x000007f9, 0x000007fa, 0x000007fb,
73 0x00000ff8, 0x00000ff9, 0x00000001, 0x00000039, 0x0000007b, 0x000000fb,
74 0x000001f8, 0x000001f9, 0x00000ffa, 0x00000ffb, 0x00001ff8, 0x00001ff9,
75 0x00001ffa, 0x00001ffb, 0x00003ff8, 0x00003ff9, 0x00003ffa, 0x00000000,
76 0x00000004, 0x0000003a, 0x000001fa, 0x00003ffb, 0x00007ff8, 0x00007ff9,
77 0x00007ffa, 0x00007ffb, 0x0000fff8, 0x0000fff9, 0x0000fffa, 0x0000fffb,
78 0x0001fff8, 0x0001fff9, 0x0001fffa, 0x00000000, 0x0000000c, 0x000000f8,
79 0x000001fb, 0x0001fffb, 0x0003fff8, 0x0003fff9, 0x0003fffa, 0x0003fffb,
80 0x0007fff8, 0x0007fff9, 0x0007fffa, 0x0007fffb, 0x000ffff8, 0x000ffff9,
81 0x000ffffa, 0x00000000, 0x0000001a, 0x000003f8, 0x000ffffb, 0x001ffff8,
82 0x001ffff9, 0x001ffffa, 0x001ffffb, 0x003ffff8, 0x003ffff9, 0x003ffffa,
83 0x003ffffb, 0x007ffff8, 0x007ffff9, 0x007ffffa, 0x007ffffb, 0x00000000,
84 0x0000003b, 0x000003f9, 0x00fffff8, 0x00fffff9, 0x00fffffa, 0x00fffffb,
85 0x01fffff8, 0x01fffff9, 0x01fffffa, 0x01fffffb, 0x03fffff8, 0x03fffff9,
86 0x03fffffa, 0x03fffffb, 0x07fffff8, 0x00000000, 0x000003fa, 0x07fffff9,
87 0x07fffffa, 0x07fffffb, 0x0ffffff8, 0x0ffffff9, 0x0ffffffa, 0x0ffffffb,
88 0x1ffffff8, 0x1ffffff9, 0x1ffffffa, 0x1ffffffb, 0x3ffffff8, 0x3ffffff9,
89 0x3ffffffa,
90 };
91
92 static const uint8_t huffbits[] = {
93 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
94 0, 0, 0, 0, 2, 4, 5, 6, 7, 7, 7, 8,
95 8, 10, 11, 11, 11, 11, 12, 12, 2, 6, 7, 8,
96 9, 9, 12, 12, 13, 13, 13, 13, 14, 14, 14, 0,
97 3, 6, 9, 14, 15, 15, 15, 15, 16, 16, 16, 16,
98 17, 17, 17, 0, 4, 8, 9, 17, 18, 18, 18, 18,
99 19, 19, 19, 19, 20, 20, 20, 0, 5, 10, 20, 21,
100 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 0,
101 6, 10, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
102 26, 26, 27, 0, 10, 27, 27, 27, 28, 28, 28, 28,
103 29, 29, 29, 29, 30, 30, 30,
104 };
105
106 static const uint8_t col_zag[64] = {
107 0, 8, 1, 2, 9, 16, 24, 17,
108 10, 3, 4, 11, 18, 25, 32, 40,
109 33, 26, 19, 12, 5, 6, 13, 20,
110 27, 34, 41, 48, 56, 49, 42, 35,
111 28, 21, 14, 7, 15, 22, 29, 36,
112 43, 50, 57, 58, 51, 44, 37, 30,
113 23, 31, 38, 45, 52, 59, 39, 46,
114 53, 60, 61, 54, 47, 55, 62, 63,
115 };
116
mimic_decode_end(AVCodecContext * avctx)117 static av_cold int mimic_decode_end(AVCodecContext *avctx)
118 {
119 MimicContext *ctx = avctx->priv_data;
120 int i;
121
122 av_freep(&ctx->swap_buf);
123 ctx->swap_buf_size = 0;
124
125 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
126 if (ctx->frames[i].f)
127 ff_thread_release_buffer(avctx, &ctx->frames[i]);
128 av_frame_free(&ctx->frames[i].f);
129 }
130
131 ff_free_vlc(&ctx->vlc);
132
133 return 0;
134 }
135
mimic_decode_init(AVCodecContext * avctx)136 static av_cold int mimic_decode_init(AVCodecContext *avctx)
137 {
138 MimicContext *ctx = avctx->priv_data;
139 int ret, i;
140
141 ctx->prev_index = 0;
142 ctx->cur_index = 15;
143
144 if ((ret = init_vlc(&ctx->vlc, 11, FF_ARRAY_ELEMS(huffbits),
145 huffbits, 1, 1, huffcodes, 4, 4, 0)) < 0) {
146 av_log(avctx, AV_LOG_ERROR, "error initializing vlc table\n");
147 return ret;
148 }
149 ff_blockdsp_init(&ctx->bdsp, avctx);
150 ff_bswapdsp_init(&ctx->bbdsp);
151 ff_hpeldsp_init(&ctx->hdsp, avctx->flags);
152 ff_idctdsp_init(&ctx->idsp, avctx);
153 ff_init_scantable(ctx->idsp.idct_permutation, &ctx->scantable, col_zag);
154
155 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
156 ctx->frames[i].f = av_frame_alloc();
157 if (!ctx->frames[i].f) {
158 mimic_decode_end(avctx);
159 return AVERROR(ENOMEM);
160 }
161 }
162
163 return 0;
164 }
165
166 #if HAVE_THREADS
mimic_decode_update_thread_context(AVCodecContext * avctx,const AVCodecContext * avctx_from)167 static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
168 {
169 MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
170 int i, ret;
171
172 if (avctx == avctx_from)
173 return 0;
174
175 dst->cur_index = src->next_cur_index;
176 dst->prev_index = src->next_prev_index;
177
178 for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
179 ff_thread_release_buffer(avctx, &dst->frames[i]);
180 if (i != src->next_cur_index && src->frames[i].f->data[0]) {
181 ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
182 if (ret < 0)
183 return ret;
184 }
185 }
186
187 return 0;
188 }
189 #endif
190
191 static const int8_t vlcdec_lookup[9][64] = {
192 { 0, },
193 { -1, 1, },
194 { -3, 3, -2, 2, },
195 { -7, 7, -6, 6, -5, 5, -4, 4, },
196 { -15, 15, -14, 14, -13, 13, -12, 12,
197 -11, 11, -10, 10, -9, 9, -8, 8, },
198 { -31, 31, -30, 30, -29, 29, -28, 28,
199 -27, 27, -26, 26, -25, 25, -24, 24,
200 -23, 23, -22, 22, -21, 21, -20, 20,
201 -19, 19, -18, 18, -17, 17, -16, 16, },
202 { -63, 63, -62, 62, -61, 61, -60, 60,
203 -59, 59, -58, 58, -57, 57, -56, 56,
204 -55, 55, -54, 54, -53, 53, -52, 52,
205 -51, 51, -50, 50, -49, 49, -48, 48,
206 -47, 47, -46, 46, -45, 45, -44, 44,
207 -43, 43, -42, 42, -41, 41, -40, 40,
208 -39, 39, -38, 38, -37, 37, -36, 36,
209 -35, 35, -34, 34, -33, 33, -32, 32, },
210 { -127, 127, -126, 126, -125, 125, -124, 124,
211 -123, 123, -122, 122, -121, 121, -120, 120,
212 -119, 119, -118, 118, -117, 117, -116, 116,
213 -115, 115, -114, 114, -113, 113, -112, 112,
214 -111, 111, -110, 110, -109, 109, -108, 108,
215 -107, 107, -106, 106, -105, 105, -104, 104,
216 -103, 103, -102, 102, -101, 101, -100, 100,
217 -99, 99, -98, 98, -97, 97, -96, 96, },
218 { -95, 95, -94, 94, -93, 93, -92, 92,
219 -91, 91, -90, 90, -89, 89, -88, 88,
220 -87, 87, -86, 86, -85, 85, -84, 84,
221 -83, 83, -82, 82, -81, 81, -80, 80,
222 -79, 79, -78, 78, -77, 77, -76, 76,
223 -75, 75, -74, 74, -73, 73, -72, 72,
224 -71, 71, -70, 70, -69, 69, -68, 68,
225 -67, 67, -66, 66, -65, 65, -64, 64, },
226 };
227
vlc_decode_block(MimicContext * ctx,int num_coeffs,int qscale)228 static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
229 {
230 int16_t *block = ctx->dct_block;
231 unsigned int pos;
232
233 ctx->bdsp.clear_block(block);
234
235 block[0] = get_bits(&ctx->gb, 8) << 3;
236
237 for (pos = 1; pos < num_coeffs; pos++) {
238 uint32_t vlc, num_bits;
239 int value;
240 int coeff;
241
242 vlc = get_vlc2(&ctx->gb, ctx->vlc.table, ctx->vlc.bits, 3);
243 if (!vlc) /* end-of-block code */
244 return 0;
245 if (vlc == -1)
246 return AVERROR_INVALIDDATA;
247
248 /* pos_add and num_bits are coded in the vlc code */
249 pos += vlc & 15; // pos_add
250 num_bits = vlc >> 4; // num_bits
251
252 if (pos >= 64)
253 return AVERROR_INVALIDDATA;
254
255 value = get_bits(&ctx->gb, num_bits);
256
257 /* FFmpeg's IDCT behaves somewhat different from the original code, so
258 * a factor of 4 was added to the input */
259
260 coeff = ((int8_t*)vlcdec_lookup[num_bits])[value];
261 if (pos < 3)
262 coeff *= 16;
263 else /* TODO Use >> 10 instead of / 1001 */
264 coeff = (coeff * qscale) / 1001;
265
266 block[ctx->scantable.permutated[pos]] = coeff;
267 }
268
269 return 0;
270 }
271
decode(MimicContext * ctx,int quality,int num_coeffs,int is_iframe)272 static int decode(MimicContext *ctx, int quality, int num_coeffs,
273 int is_iframe)
274 {
275 int ret, y, x, plane, cur_row = 0;
276
277 for (plane = 0; plane < 3; plane++) {
278 const int is_chroma = !!plane;
279 const int qscale = av_clip(10000 - quality, is_chroma ? 1000 : 2000,
280 10000) << 2;
281 const int stride = ctx->frames[ctx->cur_index ].f->linesize[plane];
282 const uint8_t *src = ctx->frames[ctx->prev_index].f->data[plane];
283 uint8_t *dst = ctx->frames[ctx->cur_index ].f->data[plane];
284
285 for (y = 0; y < ctx->num_vblocks[plane]; y++) {
286 for (x = 0; x < ctx->num_hblocks[plane]; x++) {
287 /* Check for a change condition in the current block.
288 * - iframes always change.
289 * - Luma plane changes on get_bits1 == 0
290 * - Chroma planes change on get_bits1 == 1 */
291 if (is_iframe || get_bits1(&ctx->gb) == is_chroma) {
292 /* Luma planes may use a backreference from the 15 last
293 * frames preceding the previous. (get_bits1 == 1)
294 * Chroma planes don't use backreferences. */
295 if (is_chroma || is_iframe || !get_bits1(&ctx->gb)) {
296 if ((ret = vlc_decode_block(ctx, num_coeffs,
297 qscale)) < 0) {
298 av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
299 "block.\n");
300 return ret;
301 }
302 ctx->idsp.idct_put(dst, stride, ctx->dct_block);
303 } else {
304 unsigned int backref = get_bits(&ctx->gb, 4);
305 int index = (ctx->cur_index + backref) & 15;
306 uint8_t *p = ctx->frames[index].f->data[0];
307
308 if (index != ctx->cur_index && p) {
309 ff_thread_await_progress(&ctx->frames[index],
310 cur_row, 0);
311 p += src -
312 ctx->frames[ctx->prev_index].f->data[plane];
313 ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
314 } else {
315 av_log(ctx->avctx, AV_LOG_ERROR,
316 "No such backreference! Buggy sample.\n");
317 }
318 }
319 } else {
320 ff_thread_await_progress(&ctx->frames[ctx->prev_index],
321 cur_row, 0);
322 ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8);
323 }
324 src += 8;
325 dst += 8;
326 }
327 src += (stride - ctx->num_hblocks[plane]) << 3;
328 dst += (stride - ctx->num_hblocks[plane]) << 3;
329
330 ff_thread_report_progress(&ctx->frames[ctx->cur_index],
331 cur_row++, 0);
332 }
333 }
334
335 return 0;
336 }
337
338 /**
339 * Flip the buffer upside-down and put it in the YVU order to revert the
340 * way Mimic encodes frames.
341 */
flip_swap_frame(AVFrame * f)342 static void flip_swap_frame(AVFrame *f)
343 {
344 int i;
345 uint8_t *data_1 = f->data[1];
346 f->data[0] = f->data[0] + ( f->height - 1) * f->linesize[0];
347 f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2];
348 f->data[2] = data_1 + ((f->height >> 1) - 1) * f->linesize[1];
349 for (i = 0; i < 3; i++)
350 f->linesize[i] *= -1;
351 }
352
mimic_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)353 static int mimic_decode_frame(AVCodecContext *avctx, void *data,
354 int *got_frame, AVPacket *avpkt)
355 {
356 const uint8_t *buf = avpkt->data;
357 int buf_size = avpkt->size;
358 int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
359 MimicContext *ctx = avctx->priv_data;
360 GetByteContext gb;
361 int is_pframe;
362 int width, height;
363 int quality, num_coeffs;
364 int res;
365
366 if (buf_size <= MIMIC_HEADER_SIZE) {
367 av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
368 return AVERROR_INVALIDDATA;
369 }
370
371 bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE);
372 bytestream2_skip(&gb, 2); /* some constant (always 256) */
373 quality = bytestream2_get_le16u(&gb);
374 width = bytestream2_get_le16u(&gb);
375 height = bytestream2_get_le16u(&gb);
376 bytestream2_skip(&gb, 4); /* some constant */
377 is_pframe = bytestream2_get_le32u(&gb);
378 num_coeffs = bytestream2_get_byteu(&gb);
379 bytestream2_skip(&gb, 3); /* some constant */
380
381 if (!ctx->avctx) {
382 int i;
383
384 if (!(width == 160 && height == 120) &&
385 !(width == 320 && height == 240)) {
386 av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
387 return AVERROR_INVALIDDATA;
388 }
389
390 res = ff_set_dimensions(avctx, width, height);
391 if (res < 0)
392 return res;
393
394 ctx->avctx = avctx;
395 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
396 for (i = 0; i < 3; i++) {
397 ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height, 3 + !!i);
398 ctx->num_hblocks[i] = width >> (3 + !!i);
399 }
400 } else if (width != ctx->avctx->width || height != ctx->avctx->height) {
401 avpriv_request_sample(avctx, "Resolution changing");
402 return AVERROR_PATCHWELCOME;
403 }
404
405 if (is_pframe && !ctx->frames[ctx->prev_index].f->data[0]) {
406 av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
407 return AVERROR_INVALIDDATA;
408 }
409
410 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
411 ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
412 AV_PICTURE_TYPE_I;
413 if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
414 AV_GET_BUFFER_FLAG_REF)) < 0)
415 return res;
416
417 ctx->next_prev_index = ctx->cur_index;
418 ctx->next_cur_index = (ctx->cur_index - 1) & 15;
419
420 ff_thread_finish_setup(avctx);
421
422 av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size);
423 if (!ctx->swap_buf)
424 return AVERROR(ENOMEM);
425
426 ctx->bbdsp.bswap_buf(ctx->swap_buf,
427 (const uint32_t *) (buf + MIMIC_HEADER_SIZE),
428 swap_buf_size >> 2);
429 init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);
430
431 res = decode(ctx, quality, num_coeffs, !is_pframe);
432 ff_thread_report_progress(&ctx->frames[ctx->cur_index], INT_MAX, 0);
433 if (res < 0) {
434 if (!(avctx->active_thread_type & FF_THREAD_FRAME))
435 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
436 return res;
437 }
438
439 if ((res = av_frame_ref(data, ctx->frames[ctx->cur_index].f)) < 0)
440 return res;
441 *got_frame = 1;
442
443 flip_swap_frame(data);
444
445 ctx->prev_index = ctx->next_prev_index;
446 ctx->cur_index = ctx->next_cur_index;
447
448 return buf_size;
449 }
450
451 AVCodec ff_mimic_decoder = {
452 .name = "mimic",
453 .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
454 .type = AVMEDIA_TYPE_VIDEO,
455 .id = AV_CODEC_ID_MIMIC,
456 .priv_data_size = sizeof(MimicContext),
457 .init = mimic_decode_init,
458 .close = mimic_decode_end,
459 .decode = mimic_decode_frame,
460 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
461 .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
462 .caps_internal = FF_CODEC_CAP_ALLOCATE_PROGRESS,
463 };
464