2 * Copyright (C) 2005 Ole André Vadla Ravnås <oleavr@gmail.com>
3 * Copyright (C) 2008 Ramiro Polla
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 #include "bitstream.h"
30 #include "bytestream.h"
37 #define MIMIC_HEADER_SIZE 20
39 typedef struct MimicContext {
40 AVCodecContext *avctx;
51 ThreadFrame frames [16];
53 DECLARE_ALIGNED(16, int16_t, dct_block)[64];
58 BswapDSPContext bbdsp;
63 /* Kept in the context so multithreading can have a constant to read from */
68 static const uint32_t huffcodes[] = {
69 0x0000000a, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
70 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
71 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x0000000b,
72 0x0000001b, 0x00000038, 0x00000078, 0x00000079, 0x0000007a, 0x000000f9,
73 0x000000fa, 0x000003fb, 0x000007f8, 0x000007f9, 0x000007fa, 0x000007fb,
74 0x00000ff8, 0x00000ff9, 0x00000001, 0x00000039, 0x0000007b, 0x000000fb,
75 0x000001f8, 0x000001f9, 0x00000ffa, 0x00000ffb, 0x00001ff8, 0x00001ff9,
76 0x00001ffa, 0x00001ffb, 0x00003ff8, 0x00003ff9, 0x00003ffa, 0x00000000,
77 0x00000004, 0x0000003a, 0x000001fa, 0x00003ffb, 0x00007ff8, 0x00007ff9,
78 0x00007ffa, 0x00007ffb, 0x0000fff8, 0x0000fff9, 0x0000fffa, 0x0000fffb,
79 0x0001fff8, 0x0001fff9, 0x0001fffa, 0x00000000, 0x0000000c, 0x000000f8,
80 0x000001fb, 0x0001fffb, 0x0003fff8, 0x0003fff9, 0x0003fffa, 0x0003fffb,
81 0x0007fff8, 0x0007fff9, 0x0007fffa, 0x0007fffb, 0x000ffff8, 0x000ffff9,
82 0x000ffffa, 0x00000000, 0x0000001a, 0x000003f8, 0x000ffffb, 0x001ffff8,
83 0x001ffff9, 0x001ffffa, 0x001ffffb, 0x003ffff8, 0x003ffff9, 0x003ffffa,
84 0x003ffffb, 0x007ffff8, 0x007ffff9, 0x007ffffa, 0x007ffffb, 0x00000000,
85 0x0000003b, 0x000003f9, 0x00fffff8, 0x00fffff9, 0x00fffffa, 0x00fffffb,
86 0x01fffff8, 0x01fffff9, 0x01fffffa, 0x01fffffb, 0x03fffff8, 0x03fffff9,
87 0x03fffffa, 0x03fffffb, 0x07fffff8, 0x00000000, 0x000003fa, 0x07fffff9,
88 0x07fffffa, 0x07fffffb, 0x0ffffff8, 0x0ffffff9, 0x0ffffffa, 0x0ffffffb,
89 0x1ffffff8, 0x1ffffff9, 0x1ffffffa, 0x1ffffffb, 0x3ffffff8, 0x3ffffff9,
93 static const uint8_t huffbits[] = {
94 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
95 0, 0, 0, 0, 2, 4, 5, 6, 7, 7, 7, 8,
96 8, 10, 11, 11, 11, 11, 12, 12, 2, 6, 7, 8,
97 9, 9, 12, 12, 13, 13, 13, 13, 14, 14, 14, 0,
98 3, 6, 9, 14, 15, 15, 15, 15, 16, 16, 16, 16,
99 17, 17, 17, 0, 4, 8, 9, 17, 18, 18, 18, 18,
100 19, 19, 19, 19, 20, 20, 20, 0, 5, 10, 20, 21,
101 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 0,
102 6, 10, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26,
103 26, 26, 27, 0, 10, 27, 27, 27, 28, 28, 28, 28,
104 29, 29, 29, 29, 30, 30, 30,
107 static const uint8_t col_zag[64] = {
108 0, 8, 1, 2, 9, 16, 24, 17,
109 10, 3, 4, 11, 18, 25, 32, 40,
110 33, 26, 19, 12, 5, 6, 13, 20,
111 27, 34, 41, 48, 56, 49, 42, 35,
112 28, 21, 14, 7, 15, 22, 29, 36,
113 43, 50, 57, 58, 51, 44, 37, 30,
114 23, 31, 38, 45, 52, 59, 39, 46,
115 53, 60, 61, 54, 47, 55, 62, 63,
118 static av_cold int mimic_decode_end(AVCodecContext *avctx)
120 MimicContext *ctx = avctx->priv_data;
123 av_free(ctx->swap_buf);
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);
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);
169 static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
171 MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
174 if (avctx == avctx_from)
177 dst->cur_index = src->next_cur_index;
178 dst->prev_index = src->next_prev_index;
180 for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
181 ff_thread_release_buffer(avctx, &dst->frames[i]);
182 if (src->frames[i].f->data[0]) {
183 ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
192 static const int8_t vlcdec_lookup[9][64] = {
196 { -7, 7, -6, 6, -5, 5, -4, 4, },
197 { -15, 15, -14, 14, -13, 13, -12, 12,
198 -11, 11, -10, 10, -9, 9, -8, 8, },
199 { -31, 31, -30, 30, -29, 29, -28, 28,
200 -27, 27, -26, 26, -25, 25, -24, 24,
201 -23, 23, -22, 22, -21, 21, -20, 20,
202 -19, 19, -18, 18, -17, 17, -16, 16, },
203 { -63, 63, -62, 62, -61, 61, -60, 60,
204 -59, 59, -58, 58, -57, 57, -56, 56,
205 -55, 55, -54, 54, -53, 53, -52, 52,
206 -51, 51, -50, 50, -49, 49, -48, 48,
207 -47, 47, -46, 46, -45, 45, -44, 44,
208 -43, 43, -42, 42, -41, 41, -40, 40,
209 -39, 39, -38, 38, -37, 37, -36, 36,
210 -35, 35, -34, 34, -33, 33, -32, 32, },
211 { -127, 127, -126, 126, -125, 125, -124, 124,
212 -123, 123, -122, 122, -121, 121, -120, 120,
213 -119, 119, -118, 118, -117, 117, -116, 116,
214 -115, 115, -114, 114, -113, 113, -112, 112,
215 -111, 111, -110, 110, -109, 109, -108, 108,
216 -107, 107, -106, 106, -105, 105, -104, 104,
217 -103, 103, -102, 102, -101, 101, -100, 100,
218 -99, 99, -98, 98, -97, 97, -96, 96, },
219 { -95, 95, -94, 94, -93, 93, -92, 92,
220 -91, 91, -90, 90, -89, 89, -88, 88,
221 -87, 87, -86, 86, -85, 85, -84, 84,
222 -83, 83, -82, 82, -81, 81, -80, 80,
223 -79, 79, -78, 78, -77, 77, -76, 76,
224 -75, 75, -74, 74, -73, 73, -72, 72,
225 -71, 71, -70, 70, -69, 69, -68, 68,
226 -67, 67, -66, 66, -65, 65, -64, 64, },
229 static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
231 int16_t *block = ctx->dct_block;
234 ctx->bdsp.clear_block(block);
236 block[0] = bitstream_read(&ctx->bc, 8) << 3;
238 for (pos = 1; pos < num_coeffs; pos++) {
239 uint32_t vlc, num_bits;
243 vlc = bitstream_read_vlc(&ctx->bc, ctx->vlc.table, ctx->vlc.bits, 3);
244 if (!vlc) /* end-of-block code */
247 return AVERROR_INVALIDDATA;
249 /* pos_add and num_bits are coded in the vlc code */
250 pos += vlc & 15; // pos_add
251 num_bits = vlc >> 4; // num_bits
254 return AVERROR_INVALIDDATA;
256 value = bitstream_read(&ctx->bc, num_bits);
258 /* Libav's IDCT behaves somewhat different from the original code, so
259 * a factor of 4 was added to the input */
261 coeff = vlcdec_lookup[num_bits][value];
264 else /* TODO Use >> 10 instead of / 1001 */
265 coeff = (coeff * qscale) / 1001;
267 block[ctx->scantable.permutated[pos]] = coeff;
273 static int decode(MimicContext *ctx, int quality, int num_coeffs,
276 int ret, y, x, plane, cur_row = 0;
278 for (plane = 0; plane < 3; plane++) {
279 const int is_chroma = !!plane;
280 const int qscale = av_clip(10000 - quality, is_chroma ? 1000 : 2000,
282 const int stride = ctx->frames[ctx->cur_index ].f->linesize[plane];
283 const uint8_t *src = ctx->frames[ctx->prev_index].f->data[plane];
284 uint8_t *dst = ctx->frames[ctx->cur_index ].f->data[plane];
286 for (y = 0; y < ctx->num_vblocks[plane]; y++) {
287 for (x = 0; x < ctx->num_hblocks[plane]; x++) {
288 /* Check for a change condition in the current block.
289 * - iframes always change.
290 * - Luma plane changes on bitstream_read_bit == 0
291 * - Chroma planes change on bitstream_read_bit == 1 */
292 if (is_iframe || bitstream_read_bit(&ctx->bc) == is_chroma) {
293 /* Luma planes may use a backreference from the 15 last
294 * frames preceding the previous. (bitstream_read_bit == 1)
295 * Chroma planes don't use backreferences. */
296 if (is_chroma || is_iframe || !bitstream_read_bit(&ctx->bc)) {
297 if ((ret = vlc_decode_block(ctx, num_coeffs,
299 av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
303 ctx->idsp.idct_put(dst, stride, ctx->dct_block);
305 unsigned int backref = bitstream_read(&ctx->bc, 4);
306 int index = (ctx->cur_index + backref) & 15;
307 uint8_t *p = ctx->frames[index].f->data[0];
309 if (index != ctx->cur_index && p) {
310 ff_thread_await_progress(&ctx->frames[index],
313 ctx->frames[ctx->prev_index].f->data[plane];
314 ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
316 av_log(ctx->avctx, AV_LOG_ERROR,
317 "No such backreference! Buggy sample.\n");
321 ff_thread_await_progress(&ctx->frames[ctx->prev_index],
323 ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8);
328 src += (stride - ctx->num_hblocks[plane]) << 3;
329 dst += (stride - ctx->num_hblocks[plane]) << 3;
331 ff_thread_report_progress(&ctx->frames[ctx->cur_index],
340 * Flip the buffer upside-down and put it in the YVU order to revert the
341 * way Mimic encodes frames.
343 static void flip_swap_frame(AVFrame *f)
346 uint8_t *data_1 = f->data[1];
347 f->data[0] = f->data[0] + ( f->height - 1) * f->linesize[0];
348 f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2];
349 f->data[2] = data_1 + ((f->height >> 1) - 1) * f->linesize[1];
350 for (i = 0; i < 3; i++)
351 f->linesize[i] *= -1;
354 static int mimic_decode_frame(AVCodecContext *avctx, void *data,
355 int *got_frame, AVPacket *avpkt)
357 const uint8_t *buf = avpkt->data;
358 int buf_size = avpkt->size;
359 int swap_buf_size = buf_size - MIMIC_HEADER_SIZE;
360 MimicContext *ctx = avctx->priv_data;
364 int quality, num_coeffs;
367 if (buf_size <= MIMIC_HEADER_SIZE) {
368 av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
369 return AVERROR_INVALIDDATA;
372 bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE);
373 bytestream2_skip(&gb, 2); /* some constant (always 256) */
374 quality = bytestream2_get_le16u(&gb);
375 width = bytestream2_get_le16u(&gb);
376 height = bytestream2_get_le16u(&gb);
377 bytestream2_skip(&gb, 4); /* some constant */
378 is_pframe = bytestream2_get_le32u(&gb);
379 num_coeffs = bytestream2_get_byteu(&gb);
380 bytestream2_skip(&gb, 3); /* some constant */
385 if (!(width == 160 && height == 120) &&
386 !(width == 320 && height == 240)) {
387 av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n");
388 return AVERROR_INVALIDDATA;
392 avctx->width = width;
393 avctx->height = height;
394 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
395 for (i = 0; i < 3; i++) {
396 ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height, 3 + !!i);
397 ctx->num_hblocks[i] = width >> (3 + !!i);
399 } else if (width != ctx->avctx->width || height != ctx->avctx->height) {
400 avpriv_request_sample(avctx, "Resolution changing");
401 return AVERROR_PATCHWELCOME;
404 if (is_pframe && !ctx->frames[ctx->prev_index].f->data[0]) {
405 av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
406 return AVERROR_INVALIDDATA;
409 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
410 ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
412 if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
413 AV_GET_BUFFER_FLAG_REF)) < 0) {
414 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
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 bitstream_init8(&ctx->bc, ctx->swap_buf, swap_buf_size);
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;
452 static av_cold int mimic_init_thread_copy(AVCodecContext *avctx)
454 MimicContext *ctx = avctx->priv_data;
457 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
458 ctx->frames[i].f = av_frame_alloc();
459 if (!ctx->frames[i].f) {
460 mimic_decode_end(avctx);
461 return AVERROR(ENOMEM);
468 AVCodec ff_mimic_decoder = {
470 .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
471 .type = AVMEDIA_TYPE_VIDEO,
472 .id = AV_CODEC_ID_MIMIC,
473 .priv_data_size = sizeof(MimicContext),
474 .init = mimic_decode_init,
475 .close = mimic_decode_end,
476 .decode = mimic_decode_frame,
477 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
478 .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
479 .init_thread_copy = ONLY_IF_THREADS_ENABLED(mimic_init_thread_copy),