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
26 #include "libavutil/thread.h"
32 #include "bytestream.h"
38 #define MIMIC_HEADER_SIZE 20
39 #define MIMIC_VLC_BITS 11
41 typedef struct MimicContext {
42 AVCodecContext *avctx;
53 ThreadFrame frames [16];
55 DECLARE_ALIGNED(32, int16_t, dct_block)[64];
60 BswapDSPContext bbdsp;
64 /* Kept in the context so multithreading can have a constant to read from */
71 static const uint8_t huffsyms[] = {
72 0x10, 0x20, 0x30, 0x00, 0x11, 0x40, 0x50, 0x12, 0x13, 0x21, 0x31, 0x60,
73 0x14, 0x15, 0x16, 0x22, 0x41, 0x17, 0x18, 0x23, 0x24, 0x25, 0x32, 0x42,
74 0x51, 0x61, 0x70, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x26, 0x27,
75 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x33, 0x34, 0x35, 0x36, 0x37,
76 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x43, 0x44, 0x45, 0x46, 0x47,
77 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x52, 0x53, 0x54, 0x55, 0x56,
78 0x57, 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x62, 0x63, 0x64, 0x65,
79 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x71, 0x72, 0x73,
80 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E,
83 static const uint8_t huffbits[] = {
84 2, 2, 3, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8,
85 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12,
86 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 17, 17,
87 17, 17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21,
88 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
89 26, 26, 27, 27, 27, 27, 28, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30,
92 static const uint8_t col_zag[64] = {
93 0, 8, 1, 2, 9, 16, 24, 17,
94 10, 3, 4, 11, 18, 25, 32, 40,
95 33, 26, 19, 12, 5, 6, 13, 20,
96 27, 34, 41, 48, 56, 49, 42, 35,
97 28, 21, 14, 7, 15, 22, 29, 36,
98 43, 50, 57, 58, 51, 44, 37, 30,
99 23, 31, 38, 45, 52, 59, 39, 46,
100 53, 60, 61, 54, 47, 55, 62, 63,
103 static av_cold int mimic_decode_end(AVCodecContext *avctx)
105 MimicContext *ctx = avctx->priv_data;
108 av_freep(&ctx->swap_buf);
109 ctx->swap_buf_size = 0;
111 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
112 if (ctx->frames[i].f)
113 ff_thread_release_buffer(avctx, &ctx->frames[i]);
114 av_frame_free(&ctx->frames[i].f);
120 static av_cold void mimic_init_static(void)
122 INIT_VLC_STATIC_FROM_LENGTHS(&block_vlc, MIMIC_VLC_BITS, FF_ARRAY_ELEMS(huffbits),
123 huffbits, 1, huffsyms, 1, 1, 0, 0, 4368);
126 static av_cold int mimic_decode_init(AVCodecContext *avctx)
128 static AVOnce init_static_once = AV_ONCE_INIT;
129 MimicContext *ctx = avctx->priv_data;
135 ff_blockdsp_init(&ctx->bdsp, avctx);
136 ff_bswapdsp_init(&ctx->bbdsp);
137 ff_hpeldsp_init(&ctx->hdsp, avctx->flags);
138 ff_idctdsp_init(&ctx->idsp, avctx);
139 ff_init_scantable(ctx->idsp.idct_permutation, &ctx->scantable, col_zag);
141 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
142 ctx->frames[i].f = av_frame_alloc();
143 if (!ctx->frames[i].f)
144 return AVERROR(ENOMEM);
147 ff_thread_once(&init_static_once, mimic_init_static);
153 static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
155 MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
158 if (avctx == avctx_from)
161 dst->cur_index = src->next_cur_index;
162 dst->prev_index = src->next_prev_index;
164 for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
165 ff_thread_release_buffer(avctx, &dst->frames[i]);
166 if (i != src->next_cur_index && src->frames[i].f->data[0]) {
167 ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
177 static const int8_t vlcdec_lookup[9][64] = {
181 { -7, 7, -6, 6, -5, 5, -4, 4, },
182 { -15, 15, -14, 14, -13, 13, -12, 12,
183 -11, 11, -10, 10, -9, 9, -8, 8, },
184 { -31, 31, -30, 30, -29, 29, -28, 28,
185 -27, 27, -26, 26, -25, 25, -24, 24,
186 -23, 23, -22, 22, -21, 21, -20, 20,
187 -19, 19, -18, 18, -17, 17, -16, 16, },
188 { -63, 63, -62, 62, -61, 61, -60, 60,
189 -59, 59, -58, 58, -57, 57, -56, 56,
190 -55, 55, -54, 54, -53, 53, -52, 52,
191 -51, 51, -50, 50, -49, 49, -48, 48,
192 -47, 47, -46, 46, -45, 45, -44, 44,
193 -43, 43, -42, 42, -41, 41, -40, 40,
194 -39, 39, -38, 38, -37, 37, -36, 36,
195 -35, 35, -34, 34, -33, 33, -32, 32, },
196 { -127, 127, -126, 126, -125, 125, -124, 124,
197 -123, 123, -122, 122, -121, 121, -120, 120,
198 -119, 119, -118, 118, -117, 117, -116, 116,
199 -115, 115, -114, 114, -113, 113, -112, 112,
200 -111, 111, -110, 110, -109, 109, -108, 108,
201 -107, 107, -106, 106, -105, 105, -104, 104,
202 -103, 103, -102, 102, -101, 101, -100, 100,
203 -99, 99, -98, 98, -97, 97, -96, 96, },
204 { -95, 95, -94, 94, -93, 93, -92, 92,
205 -91, 91, -90, 90, -89, 89, -88, 88,
206 -87, 87, -86, 86, -85, 85, -84, 84,
207 -83, 83, -82, 82, -81, 81, -80, 80,
208 -79, 79, -78, 78, -77, 77, -76, 76,
209 -75, 75, -74, 74, -73, 73, -72, 72,
210 -71, 71, -70, 70, -69, 69, -68, 68,
211 -67, 67, -66, 66, -65, 65, -64, 64, },
214 static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
216 int16_t *block = ctx->dct_block;
219 ctx->bdsp.clear_block(block);
221 block[0] = get_bits(&ctx->gb, 8) << 3;
223 for (pos = 1; pos < num_coeffs; pos++) {
224 uint32_t vlc, num_bits;
228 vlc = get_vlc2(&ctx->gb, block_vlc.table, MIMIC_VLC_BITS, 3);
229 if (!vlc) /* end-of-block code */
232 return AVERROR_INVALIDDATA;
234 /* pos_add and num_bits are coded in the vlc code */
235 pos += vlc & 15; // pos_add
236 num_bits = vlc >> 4; // num_bits
239 return AVERROR_INVALIDDATA;
241 value = get_bits(&ctx->gb, num_bits);
243 /* FFmpeg's IDCT behaves somewhat different from the original code, so
244 * a factor of 4 was added to the input */
246 coeff = ((int8_t*)vlcdec_lookup[num_bits])[value];
249 else /* TODO Use >> 10 instead of / 1001 */
250 coeff = (coeff * qscale) / 1001;
252 block[ctx->scantable.permutated[pos]] = coeff;
258 static int decode(MimicContext *ctx, int quality, int num_coeffs,
261 int ret, y, x, plane, cur_row = 0;
263 for (plane = 0; plane < 3; plane++) {
264 const int is_chroma = !!plane;
265 const int qscale = av_clip(10000 - quality, is_chroma ? 1000 : 2000,
267 const int stride = ctx->frames[ctx->cur_index ].f->linesize[plane];
268 const uint8_t *src = ctx->frames[ctx->prev_index].f->data[plane];
269 uint8_t *dst = ctx->frames[ctx->cur_index ].f->data[plane];
271 for (y = 0; y < ctx->num_vblocks[plane]; y++) {
272 for (x = 0; x < ctx->num_hblocks[plane]; x++) {
273 /* Check for a change condition in the current block.
274 * - iframes always change.
275 * - Luma plane changes on get_bits1 == 0
276 * - Chroma planes change on get_bits1 == 1 */
277 if (is_iframe || get_bits1(&ctx->gb) == is_chroma) {
278 /* Luma planes may use a backreference from the 15 last
279 * frames preceding the previous. (get_bits1 == 1)
280 * Chroma planes don't use backreferences. */
281 if (is_chroma || is_iframe || !get_bits1(&ctx->gb)) {
282 if ((ret = vlc_decode_block(ctx, num_coeffs,
284 av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
288 ctx->idsp.idct_put(dst, stride, ctx->dct_block);
290 unsigned int backref = get_bits(&ctx->gb, 4);
291 int index = (ctx->cur_index + backref) & 15;
292 uint8_t *p = ctx->frames[index].f->data[0];
294 if (index != ctx->cur_index && p) {
295 ff_thread_await_progress(&ctx->frames[index],
298 ctx->frames[ctx->prev_index].f->data[plane];
299 ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
301 av_log(ctx->avctx, AV_LOG_ERROR,
302 "No such backreference! Buggy sample.\n");
306 ff_thread_await_progress(&ctx->frames[ctx->prev_index],
308 ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8);
313 src += (stride - ctx->num_hblocks[plane]) << 3;
314 dst += (stride - ctx->num_hblocks[plane]) << 3;
316 ff_thread_report_progress(&ctx->frames[ctx->cur_index],
325 * Flip the buffer upside-down and put it in the YVU order to revert the
326 * way Mimic encodes frames.
328 static void flip_swap_frame(AVFrame *f)
331 uint8_t *data_1 = f->data[1];
332 f->data[0] = f->data[0] + ( f->height - 1) * f->linesize[0];
333 f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2];
334 f->data[2] = data_1 + ((f->height >> 1) - 1) * f->linesize[1];
335 for (i = 0; i < 3; i++)
336 f->linesize[i] *= -1;
339 static int mimic_decode_frame(AVCodecContext *avctx, void *data,
340 int *got_frame, AVPacket *avpkt)
342 const uint8_t *buf = avpkt->data;
343 int buf_size = avpkt->size;
344 int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
345 MimicContext *ctx = avctx->priv_data;
349 int quality, num_coeffs;
352 if (buf_size <= MIMIC_HEADER_SIZE) {
353 av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
354 return AVERROR_INVALIDDATA;
357 bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE);
358 bytestream2_skip(&gb, 2); /* some constant (always 256) */
359 quality = bytestream2_get_le16u(&gb);
360 width = bytestream2_get_le16u(&gb);
361 height = bytestream2_get_le16u(&gb);
362 bytestream2_skip(&gb, 4); /* some constant */
363 is_pframe = bytestream2_get_le32u(&gb);
364 num_coeffs = bytestream2_get_byteu(&gb);
365 bytestream2_skip(&gb, 3); /* some constant */
370 if (!(width == 160 && height == 120) &&
371 !(width == 320 && height == 240)) {
372 av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
373 return AVERROR_INVALIDDATA;
376 res = ff_set_dimensions(avctx, width, height);
381 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
382 for (i = 0; i < 3; i++) {
383 ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height, 3 + !!i);
384 ctx->num_hblocks[i] = width >> (3 + !!i);
386 } else if (width != ctx->avctx->width || height != ctx->avctx->height) {
387 avpriv_request_sample(avctx, "Resolution changing");
388 return AVERROR_PATCHWELCOME;
391 if (is_pframe && !ctx->frames[ctx->prev_index].f->data[0]) {
392 av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
393 return AVERROR_INVALIDDATA;
396 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
397 ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
399 if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
400 AV_GET_BUFFER_FLAG_REF)) < 0)
403 ctx->next_prev_index = ctx->cur_index;
404 ctx->next_cur_index = (ctx->cur_index - 1) & 15;
406 ff_thread_finish_setup(avctx);
408 av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size);
410 return AVERROR(ENOMEM);
412 ctx->bbdsp.bswap_buf(ctx->swap_buf,
413 (const uint32_t *) (buf + MIMIC_HEADER_SIZE),
415 init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);
417 res = decode(ctx, quality, num_coeffs, !is_pframe);
418 ff_thread_report_progress(&ctx->frames[ctx->cur_index], INT_MAX, 0);
420 if (!(avctx->active_thread_type & FF_THREAD_FRAME))
421 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
425 if ((res = av_frame_ref(data, ctx->frames[ctx->cur_index].f)) < 0)
429 flip_swap_frame(data);
431 ctx->prev_index = ctx->next_prev_index;
432 ctx->cur_index = ctx->next_cur_index;
437 AVCodec ff_mimic_decoder = {
439 .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
440 .type = AVMEDIA_TYPE_VIDEO,
441 .id = AV_CODEC_ID_MIMIC,
442 .priv_data_size = sizeof(MimicContext),
443 .init = mimic_decode_init,
444 .close = mimic_decode_end,
445 .decode = mimic_decode_frame,
446 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
447 .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
448 .caps_internal = FF_CODEC_CAP_ALLOCATE_PROGRESS |
449 FF_CODEC_CAP_INIT_CLEANUP | FF_CODEC_CAP_INIT_THREADSAFE,