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
29 #include "bytestream.h"
33 #define MIMIC_HEADER_SIZE 20
36 AVCodecContext *avctx;
47 AVFrame buf_ptrs [16];
48 AVPicture flipped_ptrs[16];
50 DECLARE_ALIGNED(16, DCTELEM, dct_block)[64];
57 /* Kept in the context so multithreading can have a constant to read from */
62 static const uint32_t huffcodes[] = {
63 0x0000000a, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
64 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
65 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x0000000b,
66 0x0000001b, 0x00000038, 0x00000078, 0x00000079, 0x0000007a, 0x000000f9,
67 0x000000fa, 0x000003fb, 0x000007f8, 0x000007f9, 0x000007fa, 0x000007fb,
68 0x00000ff8, 0x00000ff9, 0x00000001, 0x00000039, 0x0000007b, 0x000000fb,
69 0x000001f8, 0x000001f9, 0x00000ffa, 0x00000ffb, 0x00001ff8, 0x00001ff9,
70 0x00001ffa, 0x00001ffb, 0x00003ff8, 0x00003ff9, 0x00003ffa, 0x00000000,
71 0x00000004, 0x0000003a, 0x000001fa, 0x00003ffb, 0x00007ff8, 0x00007ff9,
72 0x00007ffa, 0x00007ffb, 0x0000fff8, 0x0000fff9, 0x0000fffa, 0x0000fffb,
73 0x0001fff8, 0x0001fff9, 0x0001fffa, 0x00000000, 0x0000000c, 0x000000f8,
74 0x000001fb, 0x0001fffb, 0x0003fff8, 0x0003fff9, 0x0003fffa, 0x0003fffb,
75 0x0007fff8, 0x0007fff9, 0x0007fffa, 0x0007fffb, 0x000ffff8, 0x000ffff9,
76 0x000ffffa, 0x00000000, 0x0000001a, 0x000003f8, 0x000ffffb, 0x001ffff8,
77 0x001ffff9, 0x001ffffa, 0x001ffffb, 0x003ffff8, 0x003ffff9, 0x003ffffa,
78 0x003ffffb, 0x007ffff8, 0x007ffff9, 0x007ffffa, 0x007ffffb, 0x00000000,
79 0x0000003b, 0x000003f9, 0x00fffff8, 0x00fffff9, 0x00fffffa, 0x00fffffb,
80 0x01fffff8, 0x01fffff9, 0x01fffffa, 0x01fffffb, 0x03fffff8, 0x03fffff9,
81 0x03fffffa, 0x03fffffb, 0x07fffff8, 0x00000000, 0x000003fa, 0x07fffff9,
82 0x07fffffa, 0x07fffffb, 0x0ffffff8, 0x0ffffff9, 0x0ffffffa, 0x0ffffffb,
83 0x1ffffff8, 0x1ffffff9, 0x1ffffffa, 0x1ffffffb, 0x3ffffff8, 0x3ffffff9,
87 static const uint8_t huffbits[] = {
88 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
89 0, 0, 0, 0, 2, 4, 5, 6, 7, 7, 7, 8,
90 8, 10, 11, 11, 11, 11, 12, 12, 2, 6, 7, 8,
91 9, 9, 12, 12, 13, 13, 13, 13, 14, 14, 14, 0,
92 3, 6, 9, 14, 15, 15, 15, 15, 16, 16, 16, 16,
93 17, 17, 17, 0, 4, 8, 9, 17, 18, 18, 18, 18,
94 19, 19, 19, 19, 20, 20, 20, 0, 5, 10, 20, 21,
95 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 0,
96 6, 10, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
97 26, 26, 27, 0, 10, 27, 27, 27, 28, 28, 28, 28,
98 29, 29, 29, 29, 30, 30, 30,
101 static const uint8_t col_zag[64] = {
102 0, 8, 1, 2, 9, 16, 24, 17,
103 10, 3, 4, 11, 18, 25, 32, 40,
104 33, 26, 19, 12, 5, 6, 13, 20,
105 27, 34, 41, 48, 56, 49, 42, 35,
106 28, 21, 14, 7, 15, 22, 29, 36,
107 43, 50, 57, 58, 51, 44, 37, 30,
108 23, 31, 38, 45, 52, 59, 39, 46,
109 53, 60, 61, 54, 47, 55, 62, 63,
112 static av_cold int mimic_decode_init(AVCodecContext *avctx)
114 MimicContext *ctx = avctx->priv_data;
119 if(init_vlc(&ctx->vlc, 11, FF_ARRAY_ELEMS(huffbits),
120 huffbits, 1, 1, huffcodes, 4, 4, 0)) {
121 av_log(avctx, AV_LOG_ERROR, "error initializing vlc table\n");
124 dsputil_init(&ctx->dsp, avctx);
125 ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable, col_zag);
130 static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
132 MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
134 if (avctx == avctx_from) return 0;
136 dst->cur_index = src->next_cur_index;
137 dst->prev_index = src->next_prev_index;
139 memcpy(dst->buf_ptrs, src->buf_ptrs, sizeof(src->buf_ptrs));
140 memcpy(dst->flipped_ptrs, src->flipped_ptrs, sizeof(src->flipped_ptrs));
142 memset(&dst->buf_ptrs[dst->cur_index], 0, sizeof(AVFrame));
147 static const int8_t vlcdec_lookup[9][64] = {
151 { -7, 7, -6, 6, -5, 5, -4, 4, },
152 { -15, 15, -14, 14, -13, 13, -12, 12,
153 -11, 11, -10, 10, -9, 9, -8, 8, },
154 { -31, 31, -30, 30, -29, 29, -28, 28,
155 -27, 27, -26, 26, -25, 25, -24, 24,
156 -23, 23, -22, 22, -21, 21, -20, 20,
157 -19, 19, -18, 18, -17, 17, -16, 16, },
158 { -63, 63, -62, 62, -61, 61, -60, 60,
159 -59, 59, -58, 58, -57, 57, -56, 56,
160 -55, 55, -54, 54, -53, 53, -52, 52,
161 -51, 51, -50, 50, -49, 49, -48, 48,
162 -47, 47, -46, 46, -45, 45, -44, 44,
163 -43, 43, -42, 42, -41, 41, -40, 40,
164 -39, 39, -38, 38, -37, 37, -36, 36,
165 -35, 35, -34, 34, -33, 33, -32, 32, },
166 { -127, 127, -126, 126, -125, 125, -124, 124,
167 -123, 123, -122, 122, -121, 121, -120, 120,
168 -119, 119, -118, 118, -117, 117, -116, 116,
169 -115, 115, -114, 114, -113, 113, -112, 112,
170 -111, 111, -110, 110, -109, 109, -108, 108,
171 -107, 107, -106, 106, -105, 105, -104, 104,
172 -103, 103, -102, 102, -101, 101, -100, 100,
173 -99, 99, -98, 98, -97, 97, -96, 96, },
174 { -95, 95, -94, 94, -93, 93, -92, 92,
175 -91, 91, -90, 90, -89, 89, -88, 88,
176 -87, 87, -86, 86, -85, 85, -84, 84,
177 -83, 83, -82, 82, -81, 81, -80, 80,
178 -79, 79, -78, 78, -77, 77, -76, 76,
179 -75, 75, -74, 74, -73, 73, -72, 72,
180 -71, 71, -70, 70, -69, 69, -68, 68,
181 -67, 67, -66, 66, -65, 65, -64, 64, },
184 static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
186 DCTELEM *block = ctx->dct_block;
189 ctx->dsp.clear_block(block);
191 block[0] = get_bits(&ctx->gb, 8) << 3;
193 for(pos = 1; pos < num_coeffs; pos++) {
194 uint32_t vlc, num_bits;
198 vlc = get_vlc2(&ctx->gb, ctx->vlc.table, ctx->vlc.bits, 3);
199 if(!vlc) /* end-of-block code */
204 /* pos_add and num_bits are coded in the vlc code */
205 pos += vlc&15; // pos_add
206 num_bits = vlc>>4; // num_bits
211 value = get_bits(&ctx->gb, num_bits);
213 /* FFmpeg's IDCT behaves somewhat different from the original code, so
214 * a factor of 4 was added to the input */
216 coeff = vlcdec_lookup[num_bits][value];
219 else /* TODO Use >> 10 instead of / 1001 */
220 coeff = (coeff * qscale) / 1001;
222 block[ctx->scantable.permutated[pos]] = coeff;
228 static int decode(MimicContext *ctx, int quality, int num_coeffs,
231 int y, x, plane, cur_row = 0;
233 for(plane = 0; plane < 3; plane++) {
234 const int is_chroma = !!plane;
235 const int qscale = av_clip(10000-quality,is_chroma?1000:2000,10000)<<2;
236 const int stride = ctx->flipped_ptrs[ctx->cur_index].linesize[plane];
237 const uint8_t *src = ctx->flipped_ptrs[ctx->prev_index].data[plane];
238 uint8_t *dst = ctx->flipped_ptrs[ctx->cur_index ].data[plane];
240 for(y = 0; y < ctx->num_vblocks[plane]; y++) {
241 for(x = 0; x < ctx->num_hblocks[plane]; x++) {
243 /* Check for a change condition in the current block.
244 * - iframes always change.
245 * - Luma plane changes on get_bits1 == 0
246 * - Chroma planes change on get_bits1 == 1 */
247 if(is_iframe || get_bits1(&ctx->gb) == is_chroma) {
249 /* Luma planes may use a backreference from the 15 last
250 * frames preceding the previous. (get_bits1 == 1)
251 * Chroma planes don't use backreferences. */
252 if(is_chroma || is_iframe || !get_bits1(&ctx->gb)) {
254 if(!vlc_decode_block(ctx, num_coeffs, qscale))
256 ctx->dsp.idct_put(dst, stride, ctx->dct_block);
258 unsigned int backref = get_bits(&ctx->gb, 4);
259 int index = (ctx->cur_index+backref)&15;
260 uint8_t *p = ctx->flipped_ptrs[index].data[0];
262 ff_thread_await_progress(&ctx->buf_ptrs[index], cur_row, 0);
265 ctx->flipped_ptrs[ctx->prev_index].data[plane];
266 ctx->dsp.put_pixels_tab[1][0](dst, p, stride, 8);
268 av_log(ctx->avctx, AV_LOG_ERROR,
269 "No such backreference! Buggy sample.\n");
273 ff_thread_await_progress(&ctx->buf_ptrs[ctx->prev_index], cur_row, 0);
274 ctx->dsp.put_pixels_tab[1][0](dst, src, stride, 8);
279 src += (stride - ctx->num_hblocks[plane])<<3;
280 dst += (stride - ctx->num_hblocks[plane])<<3;
282 ff_thread_report_progress(&ctx->buf_ptrs[ctx->cur_index], cur_row++, 0);
290 * Flip the buffer upside-down and put it in the YVU order to match the
291 * way Mimic encodes frames.
293 static void prepare_avpic(MimicContext *ctx, AVPicture *dst, AVPicture *src)
296 dst->data[0] = src->data[0]+( ctx->avctx->height -1)*src->linesize[0];
297 dst->data[1] = src->data[2]+((ctx->avctx->height>>1)-1)*src->linesize[2];
298 dst->data[2] = src->data[1]+((ctx->avctx->height>>1)-1)*src->linesize[1];
299 for(i = 0; i < 3; i++)
300 dst->linesize[i] = -src->linesize[i];
303 static int mimic_decode_frame(AVCodecContext *avctx, void *data,
304 int *data_size, AVPacket *avpkt)
306 const uint8_t *buf = avpkt->data;
307 int buf_size = avpkt->size;
308 MimicContext *ctx = avctx->priv_data;
311 int quality, num_coeffs;
312 int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
314 if(buf_size < MIMIC_HEADER_SIZE) {
315 av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
319 buf += 2; /* some constant (always 256) */
320 quality = bytestream_get_le16(&buf);
321 width = bytestream_get_le16(&buf);
322 height = bytestream_get_le16(&buf);
323 buf += 4; /* some constant */
324 is_pframe = bytestream_get_le32(&buf);
325 num_coeffs = bytestream_get_byte(&buf);
326 buf += 3; /* some constant */
331 if(!(width == 160 && height == 120) &&
332 !(width == 320 && height == 240)) {
333 av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
338 avctx->width = width;
339 avctx->height = height;
340 avctx->pix_fmt = PIX_FMT_YUV420P;
341 for(i = 0; i < 3; i++) {
342 ctx->num_vblocks[i] = -((-height) >> (3 + !!i));
343 ctx->num_hblocks[i] = width >> (3 + !!i) ;
345 } else if(width != ctx->avctx->width || height != ctx->avctx->height) {
346 av_log(avctx, AV_LOG_ERROR, "resolution changing is not supported\n");
350 if(is_pframe && !ctx->buf_ptrs[ctx->prev_index].data[0]) {
351 av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
355 ctx->buf_ptrs[ctx->cur_index].reference = 3;
356 ctx->buf_ptrs[ctx->cur_index].pict_type = is_pframe ? AV_PICTURE_TYPE_P:AV_PICTURE_TYPE_I;
357 if(ff_thread_get_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index])) {
358 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
362 ctx->next_prev_index = ctx->cur_index;
363 ctx->next_cur_index = (ctx->cur_index - 1) & 15;
365 prepare_avpic(ctx, &ctx->flipped_ptrs[ctx->cur_index],
366 (AVPicture*) &ctx->buf_ptrs[ctx->cur_index]);
368 ff_thread_finish_setup(avctx);
370 av_fast_malloc(&ctx->swap_buf, &ctx->swap_buf_size,
371 swap_buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
373 return AVERROR(ENOMEM);
375 ctx->dsp.bswap_buf(ctx->swap_buf,
376 (const uint32_t*) buf,
378 init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3);
380 if(!decode(ctx, quality, num_coeffs, !is_pframe)) {
381 if (avctx->active_thread_type&FF_THREAD_FRAME)
382 ff_thread_report_progress(&ctx->buf_ptrs[ctx->cur_index], INT_MAX, 0);
384 ff_thread_release_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index]);
389 *(AVFrame*)data = ctx->buf_ptrs[ctx->cur_index];
390 *data_size = sizeof(AVFrame);
392 ctx->prev_index = ctx->next_prev_index;
393 ctx->cur_index = ctx->next_cur_index;
395 /* Only release frames that aren't used for backreferences anymore */
396 if(ctx->buf_ptrs[ctx->cur_index].data[0])
397 ff_thread_release_buffer(avctx, &ctx->buf_ptrs[ctx->cur_index]);
402 static av_cold int mimic_decode_end(AVCodecContext *avctx)
404 MimicContext *ctx = avctx->priv_data;
407 av_free(ctx->swap_buf);
409 if (avctx->internal->is_copy)
412 for(i = 0; i < 16; i++)
413 if(ctx->buf_ptrs[i].data[0])
414 ff_thread_release_buffer(avctx, &ctx->buf_ptrs[i]);
420 AVCodec ff_mimic_decoder = {
422 .type = AVMEDIA_TYPE_VIDEO,
423 .id = CODEC_ID_MIMIC,
424 .priv_data_size = sizeof(MimicContext),
425 .init = mimic_decode_init,
426 .close = mimic_decode_end,
427 .decode = mimic_decode_frame,
428 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
429 .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
430 .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context)