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"
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_free(ctx->swap_buf);
124 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
125 if (ctx->frames[i].f)
126 ff_thread_release_buffer(avctx, &ctx->frames[i]);
127 av_frame_free(&ctx->frames[i].f);
130 if (!avctx->internal->is_copy)
131 ff_free_vlc(&ctx->vlc);
136 static av_cold int mimic_decode_init(AVCodecContext *avctx)
138 MimicContext *ctx = avctx->priv_data;
141 avctx->internal->allocate_progress = 1;
146 if ((ret = init_vlc(&ctx->vlc, 11, FF_ARRAY_ELEMS(huffbits),
147 huffbits, 1, 1, huffcodes, 4, 4, 0)) < 0) {
148 av_log(avctx, AV_LOG_ERROR, "error initializing vlc table\n");
151 ff_blockdsp_init(&ctx->bdsp, avctx);
152 ff_bswapdsp_init(&ctx->bbdsp);
153 ff_hpeldsp_init(&ctx->hdsp, avctx->flags);
154 ff_idctdsp_init(&ctx->idsp, avctx);
155 ff_init_scantable(ctx->idsp.idct_permutation, &ctx->scantable, col_zag);
157 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
158 ctx->frames[i].f = av_frame_alloc();
159 if (!ctx->frames[i].f) {
160 mimic_decode_end(avctx);
161 return AVERROR(ENOMEM);
168 static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
170 MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data;
173 if (avctx == avctx_from)
176 dst->cur_index = src->next_cur_index;
177 dst->prev_index = src->next_prev_index;
179 for (i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) {
180 ff_thread_release_buffer(avctx, &dst->frames[i]);
181 if (src->frames[i].f->data[0]) {
182 ret = ff_thread_ref_frame(&dst->frames[i], &src->frames[i]);
191 static const int8_t vlcdec_lookup[9][64] = {
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, },
228 static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale)
230 int16_t *block = ctx->dct_block;
233 ctx->bdsp.clear_block(block);
235 block[0] = bitstream_read(&ctx->bc, 8) << 3;
237 for (pos = 1; pos < num_coeffs; pos++) {
238 uint32_t vlc, num_bits;
242 vlc = bitstream_read_vlc(&ctx->bc, ctx->vlc.table, ctx->vlc.bits, 3);
243 if (!vlc) /* end-of-block code */
246 return AVERROR_INVALIDDATA;
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
253 return AVERROR_INVALIDDATA;
255 value = bitstream_read(&ctx->bc, num_bits);
257 /* Libav's IDCT behaves somewhat different from the original code, so
258 * a factor of 4 was added to the input */
260 coeff = vlcdec_lookup[num_bits][value];
263 else /* TODO Use >> 10 instead of / 1001 */
264 coeff = (coeff * qscale) / 1001;
266 block[ctx->scantable.permutated[pos]] = coeff;
272 static int decode(MimicContext *ctx, int quality, int num_coeffs,
275 int ret, y, x, plane, cur_row = 0;
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,
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];
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 bitstream_read_bit == 0
290 * - Chroma planes change on bitstream_read_bit == 1 */
291 if (is_iframe || bitstream_read_bit(&ctx->bc) == is_chroma) {
292 /* Luma planes may use a backreference from the 15 last
293 * frames preceding the previous. (bitstream_read_bit == 1)
294 * Chroma planes don't use backreferences. */
295 if (is_chroma || is_iframe || !bitstream_read_bit(&ctx->bc)) {
296 if ((ret = vlc_decode_block(ctx, num_coeffs,
298 av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding "
302 ctx->idsp.idct_put(dst, stride, ctx->dct_block);
304 unsigned int backref = bitstream_read(&ctx->bc, 4);
305 int index = (ctx->cur_index + backref) & 15;
306 uint8_t *p = ctx->frames[index].f->data[0];
308 if (index != ctx->cur_index && p) {
309 ff_thread_await_progress(&ctx->frames[index],
312 ctx->frames[ctx->prev_index].f->data[plane];
313 ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8);
315 av_log(ctx->avctx, AV_LOG_ERROR,
316 "No such backreference! Buggy sample.\n");
320 ff_thread_await_progress(&ctx->frames[ctx->prev_index],
322 ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8);
327 src += (stride - ctx->num_hblocks[plane]) << 3;
328 dst += (stride - ctx->num_hblocks[plane]) << 3;
330 ff_thread_report_progress(&ctx->frames[ctx->cur_index],
339 * Flip the buffer upside-down and put it in the YVU order to revert the
340 * way Mimic encodes frames.
342 static void flip_swap_frame(AVFrame *f)
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;
353 static int mimic_decode_frame(AVCodecContext *avctx, void *data,
354 int *got_frame, AVPacket *avpkt)
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;
363 int quality, num_coeffs;
366 if (buf_size <= MIMIC_HEADER_SIZE) {
367 av_log(avctx, AV_LOG_ERROR, "insufficient data\n");
368 return AVERROR_INVALIDDATA;
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 */
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;
391 avctx->width = width;
392 avctx->height = height;
393 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
394 for (i = 0; i < 3; i++) {
395 ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height, 3 + !!i);
396 ctx->num_hblocks[i] = width >> (3 + !!i);
398 } else if (width != ctx->avctx->width || height != ctx->avctx->height) {
399 avpriv_request_sample(avctx, "Resolution changing");
400 return AVERROR_PATCHWELCOME;
403 if (is_pframe && !ctx->frames[ctx->prev_index].f->data[0]) {
404 av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n");
405 return AVERROR_INVALIDDATA;
408 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
409 ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P :
411 if ((res = ff_thread_get_buffer(avctx, &ctx->frames[ctx->cur_index],
412 AV_GET_BUFFER_FLAG_REF)) < 0) {
413 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
417 ctx->next_prev_index = ctx->cur_index;
418 ctx->next_cur_index = (ctx->cur_index - 1) & 15;
420 ff_thread_finish_setup(avctx);
422 av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size);
424 return AVERROR(ENOMEM);
426 ctx->bbdsp.bswap_buf(ctx->swap_buf,
427 (const uint32_t *) (buf + MIMIC_HEADER_SIZE),
429 bitstream_init8(&ctx->bc, ctx->swap_buf, swap_buf_size);
431 res = decode(ctx, quality, num_coeffs, !is_pframe);
432 ff_thread_report_progress(&ctx->frames[ctx->cur_index], INT_MAX, 0);
434 if (!(avctx->active_thread_type & FF_THREAD_FRAME))
435 ff_thread_release_buffer(avctx, &ctx->frames[ctx->cur_index]);
439 if ((res = av_frame_ref(data, ctx->frames[ctx->cur_index].f)) < 0)
443 flip_swap_frame(data);
445 ctx->prev_index = ctx->next_prev_index;
446 ctx->cur_index = ctx->next_cur_index;
451 static av_cold int mimic_init_thread_copy(AVCodecContext *avctx)
453 MimicContext *ctx = avctx->priv_data;
456 for (i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) {
457 ctx->frames[i].f = av_frame_alloc();
458 if (!ctx->frames[i].f) {
459 mimic_decode_end(avctx);
460 return AVERROR(ENOMEM);
467 AVCodec ff_mimic_decoder = {
469 .long_name = NULL_IF_CONFIG_SMALL("Mimic"),
470 .type = AVMEDIA_TYPE_VIDEO,
471 .id = AV_CODEC_ID_MIMIC,
472 .priv_data_size = sizeof(MimicContext),
473 .init = mimic_decode_init,
474 .close = mimic_decode_end,
475 .decode = mimic_decode_frame,
476 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
477 .update_thread_context = ONLY_IF_THREADS_ENABLED(mimic_decode_update_thread_context),
478 .init_thread_copy = ONLY_IF_THREADS_ENABLED(mimic_init_thread_copy),