2 * Copyright (C) 2005 Ole André Vadla Ravnås <oleavr@gmail.com>
3 * Copyright (C) 2008 Ramiro Polla
5 * This file is part of FFmpeg.
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.
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.
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
30 #include "bytestream.h"
36 #define MIMIC_HEADER_SIZE 20
38 typedef struct MimicContext {
39 AVCodecContext *avctx;
50 ThreadFrame frames [16];
52 DECLARE_ALIGNED(16, int16_t, dct_block)[64];
57 BswapDSPContext bbdsp;
62 /* Kept in the context so multithreading can have a constant to read from */
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,
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,
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,
117 static av_cold int mimic_decode_end(AVCodecContext *avctx)
119 MimicContext *ctx = avctx->priv_data;
122 av_freep(&ctx->swap_buf);
123 ctx->swap_buf_size = 0;
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);
131 if (!avctx->internal->is_copy)
132 ff_free_vlc(&ctx->vlc);
137 static av_cold int mimic_decode_init(AVCodecContext *avctx)
139 MimicContext *ctx = avctx->priv_data;
142 avctx->internal->allocate_progress = 1;
147 if ((ret = init_vlc(&ctx->vlc, 11, FF_ARRAY_ELEMS(huffbits),
148 huffbits, 1, 1, huffcodes, 4, 4, 0)) < 0) {
149 av_log(avctx, AV_LOG_ERROR, "error initializing vlc table\n");
152 ff_blockdsp_init(&ctx->bdsp, avctx);
153 ff_bswapdsp_init(&ctx->bbdsp);
154 ff_hpeldsp_init(&ctx->hdsp, avctx->flags);
155 ff_idctdsp_init(&ctx->idsp, avctx);
156 ff_init_scantable(ctx->idsp.idct_permutation, &ctx->scantable, col_zag);
158 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
159 ctx->frames[i].f = av_frame_alloc();
160 if (!ctx->frames[i].f) {
161 mimic_decode_end(avctx);
162 return AVERROR(ENOMEM);
170 static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
172 MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
175 if (avctx == avctx_from)
178 dst->cur_index = src->next_cur_index;
179 dst->prev_index = src->next_prev_index;
181 for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
182 ff_thread_release_buffer(avctx, &dst->frames[i]);
183 if (i != src->next_cur_index && src->frames[i].f->data[0]) {
184 ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
194 static const int8_t vlcdec_lookup[9][64] = {
198 { -7, 7, -6, 6, -5, 5, -4, 4, },
199 { -15, 15, -14, 14, -13, 13, -12, 12,
200 -11, 11, -10, 10, -9, 9, -8, 8, },
201 { -31, 31, -30, 30, -29, 29, -28, 28,
202 -27, 27, -26, 26, -25, 25, -24, 24,
203 -23, 23, -22, 22, -21, 21, -20, 20,
204 -19, 19, -18, 18, -17, 17, -16, 16, },
205 { -63, 63, -62, 62, -61, 61, -60, 60,
206 -59, 59, -58, 58, -57, 57, -56, 56,
207 -55, 55, -54, 54, -53, 53, -52, 52,
208 -51, 51, -50, 50, -49, 49, -48, 48,
209 -47, 47, -46, 46, -45, 45, -44, 44,
210 -43, 43, -42, 42, -41, 41, -40, 40,
211 -39, 39, -38, 38, -37, 37, -36, 36,
212 -35, 35, -34, 34, -33, 33, -32, 32, },
213 { -127, 127, -126, 126, -125, 125, -124, 124,
214 -123, 123, -122, 122, -121, 121, -120, 120,
215 -119, 119, -118, 118, -117, 117, -116, 116,
216 -115, 115, -114, 114, -113, 113, -112, 112,
217 -111, 111, -110, 110, -109, 109, -108, 108,
218 -107, 107, -106, 106, -105, 105, -104, 104,
219 -103, 103, -102, 102, -101, 101, -100, 100,
220 -99, 99, -98, 98, -97, 97, -96, 96, },
221 { -95, 95, -94, 94, -93, 93, -92, 92,
222 -91, 91, -90, 90, -89, 89, -88, 88,
223 -87, 87, -86, 86, -85, 85, -84, 84,
224 -83, 83, -82, 82, -81, 81, -80, 80,
225 -79, 79, -78, 78, -77, 77, -76, 76,
226 -75, 75, -74, 74, -73, 73, -72, 72,
227 -71, 71, -70, 70, -69, 69, -68, 68,
228 -67, 67, -66, 66, -65, 65, -64, 64, },
231 static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
233 int16_t *block = ctx->dct_block;
236 ctx->bdsp.clear_block(block);
238 block[0] = get_bits(&ctx->gb, 8) << 3;
240 for (pos = 1; pos < num_coeffs; pos++) {
241 uint32_t vlc, num_bits;
245 vlc = get_vlc2(&ctx->gb, ctx->vlc.table, ctx->vlc.bits, 3);
246 if (!vlc) /* end-of-block code */
249 return AVERROR_INVALIDDATA;
251 /* pos_add and num_bits are coded in the vlc code */
252 pos += vlc & 15; // pos_add
253 num_bits = vlc >> 4; // num_bits
256 return AVERROR_INVALIDDATA;
258 value = get_bits(&ctx->gb, num_bits);
260 /* FFmpeg's IDCT behaves somewhat different from the original code, so
261 * a factor of 4 was added to the input */
263 coeff = vlcdec_lookup[num_bits][value];
266 else /* TODO Use >> 10 instead of / 1001 */
267 coeff = (coeff * qscale) / 1001;
269 block[ctx->scantable.permutated[pos]] = coeff;
275 static int decode(MimicContext *ctx, int quality, int num_coeffs,
278 int ret, y, x, plane, cur_row = 0;
280 for (plane = 0; plane < 3; plane++) {
281 const int is_chroma = !!plane;
282 const int qscale = av_clip(10000 - quality, is_chroma ? 1000 : 2000,
284 const int stride = ctx->frames[ctx->cur_index ].f->linesize[plane];
285 const uint8_t *src = ctx->frames[ctx->prev_index].f->data[plane];
286 uint8_t *dst = ctx->frames[ctx->cur_index ].f->data[plane];
288 for (y = 0; y < ctx->num_vblocks[plane]; y++) {
289 for (x = 0; x < ctx->num_hblocks[plane]; x++) {
290 /* Check for a change condition in the current block.
291 * - iframes always change.
292 * - Luma plane changes on get_bits1 == 0
293 * - Chroma planes change on get_bits1 == 1 */
294 if (is_iframe || get_bits1(&ctx->gb) == is_chroma) {
295 /* Luma planes may use a backreference from the 15 last
296 * frames preceding the previous. (get_bits1 == 1)
297 * Chroma planes don't use backreferences. */
298 if (is_chroma || is_iframe || !get_bits1(&ctx->gb)) {
299 if ((ret = vlc_decode_block(ctx, num_coeffs,
301 av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
305 ctx->idsp.idct_put(dst, stride, ctx->dct_block);
307 unsigned int backref = get_bits(&ctx->gb, 4);
308 int index = (ctx->cur_index + backref) & 15;
309 uint8_t *p = ctx->frames[index].f->data[0];
311 if (index != ctx->cur_index && p) {
312 ff_thread_await_progress(&ctx->frames[index],
315 ctx->frames[ctx->prev_index].f->data[plane];
316 ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
318 av_log(ctx->avctx, AV_LOG_ERROR,
319 "No such backreference! Buggy sample.\n");
323 ff_thread_await_progress(&ctx->frames[ctx->prev_index],
325 ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8);
330 src += (stride - ctx->num_hblocks[plane]) << 3;
331 dst += (stride - ctx->num_hblocks[plane]) << 3;
333 ff_thread_report_progress(&ctx->frames[ctx->cur_index],
342 * Flip the buffer upside-down and put it in the YVU order to revert the
343 * way Mimic encodes frames.
345 static void flip_swap_frame(AVFrame *f)
348 uint8_t *data_1 = f->data[1];
349 f->data[0] = f->data[0] + ( f->height - 1) * f->linesize[0];
350 f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2];
351 f->data[2] = data_1 + ((f->height >> 1) - 1) * f->linesize[1];
352 for (i = 0; i < 3; i++)
353 f->linesize[i] *= -1;
356 static int mimic_decode_frame(AVCodecContext *avctx, void *data,
357 int *got_frame, AVPacket *avpkt)
359 const uint8_t *buf = avpkt->data;
360 int buf_size = avpkt->size;
361 int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
362 MimicContext *ctx = avctx->priv_data;
366 int quality, num_coeffs;
369 if (buf_size <= MIMIC_HEADER_SIZE) {
370 av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
371 return AVERROR_INVALIDDATA;
374 bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE);
375 bytestream2_skip(&gb, 2); /* some constant (always 256) */
376 quality = bytestream2_get_le16u(&gb);
377 width = bytestream2_get_le16u(&gb);
378 height = bytestream2_get_le16u(&gb);
379 bytestream2_skip(&gb, 4); /* some constant */
380 is_pframe = bytestream2_get_le32u(&gb);
381 num_coeffs = bytestream2_get_byteu(&gb);
382 bytestream2_skip(&gb, 3); /* some constant */
387 if (!(width == 160 && height == 120) &&
388 !(width == 320 && height == 240)) {
389 av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
390 return AVERROR_INVALIDDATA;
394 avctx->width = width;
395 avctx->height = height;
396 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
397 for (i = 0; i < 3; i++) {
398 ctx->num_vblocks[i] = FF_CEIL_RSHIFT(height, 3 + !!i);
399 ctx->num_hblocks[i] = width >> (3 + !!i);
401 } else if (width != ctx->avctx->width || height != ctx->avctx->height) {
402 avpriv_request_sample(avctx, "Resolution changing");
403 return AVERROR_PATCHWELCOME;
406 if (is_pframe && !ctx->frames[ctx->prev_index].f->data[0]) {
407 av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
408 return AVERROR_INVALIDDATA;
411 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
412 ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
414 if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
415 AV_GET_BUFFER_FLAG_REF)) < 0)
418 ctx->next_prev_index = ctx->cur_index;
419 ctx->next_cur_index = (ctx->cur_index - 1) & 15;
421 ff_thread_finish_setup(avctx);
423 av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size);
425 return AVERROR(ENOMEM);
427 ctx->bbdsp.bswap_buf(ctx->swap_buf,
428 (const uint32_t *) (buf + MIMIC_HEADER_SIZE),
430 init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);
432 res = decode(ctx, quality, num_coeffs, !is_pframe);
433 ff_thread_report_progress(&ctx->frames[ctx->cur_index], INT_MAX, 0);
435 if (!(avctx->active_thread_type & FF_THREAD_FRAME))
436 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
440 if ((res = av_frame_ref(data, ctx->frames[ctx->cur_index].f)) < 0)
444 flip_swap_frame(data);
446 ctx->prev_index = ctx->next_prev_index;
447 ctx->cur_index = ctx->next_cur_index;
449 /* Only release frames that aren't used for backreferences anymore */
450 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
456 static av_cold int mimic_init_thread_copy(AVCodecContext *avctx)
458 MimicContext *ctx = avctx->priv_data;
461 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
462 ctx->frames[i].f = av_frame_alloc();
463 if (!ctx->frames[i].f) {
464 mimic_decode_end(avctx);
465 return AVERROR(ENOMEM);
473 AVCodec ff_mimic_decoder = {
475 .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
476 .type = AVMEDIA_TYPE_VIDEO,
477 .id = AV_CODEC_ID_MIMIC,
478 .priv_data_size = sizeof(MimicContext),
479 .init = mimic_decode_init,
480 .close = mimic_decode_end,
481 .decode = mimic_decode_frame,
482 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
483 .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
484 .init_thread_copy = ONLY_IF_THREADS_ENABLED(mimic_init_thread_copy),