1 /*
2 * Electronic Arts Madcow Video Decoder
3 * Copyright (c) 2007-2009 Peter Ross
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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 St, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * Electronic Arts Madcow Video Decoder
25 * @author Peter Ross <pross@xvid.org>
26 *
27 * @see technical details at
28 * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_MAD
29 */
30
31 #include "libavutil/mem_internal.h"
32
33 #include "avcodec.h"
34 #include "blockdsp.h"
35 #include "bytestream.h"
36 #include "bswapdsp.h"
37 #include "codec_internal.h"
38 #include "get_bits.h"
39 #include "aandcttab.h"
40 #include "eaidct.h"
41 #include "idctdsp.h"
42 #include "internal.h"
43 #include "mpeg12data.h"
44 #include "mpeg12vlc.h"
45
46 #define EA_PREAMBLE_SIZE 8
47 #define MADk_TAG MKTAG('M', 'A', 'D', 'k') /* MAD I-frame */
48 #define MADm_TAG MKTAG('M', 'A', 'D', 'm') /* MAD P-frame */
49 #define MADe_TAG MKTAG('M', 'A', 'D', 'e') /* MAD lqp-frame */
50
51 typedef struct MadContext {
52 AVCodecContext *avctx;
53 BlockDSPContext bdsp;
54 BswapDSPContext bbdsp;
55 IDCTDSPContext idsp;
56 AVFrame *last_frame;
57 GetBitContext gb;
58 void *bitstream_buf;
59 unsigned int bitstream_buf_size;
60 DECLARE_ALIGNED(32, int16_t, block)[64];
61 ScanTable scantable;
62 uint16_t quant_matrix[64];
63 int mb_x;
64 int mb_y;
65 } MadContext;
66
decode_init(AVCodecContext * avctx)67 static av_cold int decode_init(AVCodecContext *avctx)
68 {
69 MadContext *s = avctx->priv_data;
70 s->avctx = avctx;
71 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
72 ff_blockdsp_init(&s->bdsp, avctx);
73 ff_bswapdsp_init(&s->bbdsp);
74 ff_idctdsp_init(&s->idsp, avctx);
75 ff_init_scantable_permutation(s->idsp.idct_permutation, FF_IDCT_PERM_NONE);
76 ff_init_scantable(s->idsp.idct_permutation, &s->scantable, ff_zigzag_direct);
77 ff_mpeg12_init_vlcs();
78
79 s->last_frame = av_frame_alloc();
80 if (!s->last_frame)
81 return AVERROR(ENOMEM);
82
83 return 0;
84 }
85
comp(unsigned char * dst,ptrdiff_t dst_stride,unsigned char * src,ptrdiff_t src_stride,int add)86 static inline void comp(unsigned char *dst, ptrdiff_t dst_stride,
87 unsigned char *src, ptrdiff_t src_stride, int add)
88 {
89 int j, i;
90 for (j=0; j<8; j++)
91 for (i=0; i<8; i++)
92 dst[j*dst_stride + i] = av_clip_uint8(src[j*src_stride + i] + add);
93 }
94
comp_block(MadContext * t,AVFrame * frame,int mb_x,int mb_y,int j,int mv_x,int mv_y,int add)95 static inline void comp_block(MadContext *t, AVFrame *frame,
96 int mb_x, int mb_y,
97 int j, int mv_x, int mv_y, int add)
98 {
99 if (j < 4) {
100 unsigned offset = (mb_y*16 + ((j&2)<<2) + mv_y)*t->last_frame->linesize[0] + mb_x*16 + ((j&1)<<3) + mv_x;
101 if (offset >= (t->avctx->height - 7) * t->last_frame->linesize[0] - 7)
102 return;
103 comp(frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
104 frame->linesize[0],
105 t->last_frame->data[0] + offset,
106 t->last_frame->linesize[0], add);
107 } else if (!(t->avctx->flags & AV_CODEC_FLAG_GRAY)) {
108 int index = j - 3;
109 unsigned offset = (mb_y * 8 + (mv_y/2))*t->last_frame->linesize[index] + mb_x * 8 + (mv_x/2);
110 if (offset >= (t->avctx->height/2 - 7) * t->last_frame->linesize[index] - 7)
111 return;
112 comp(frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x * 8,
113 frame->linesize[index],
114 t->last_frame->data[index] + offset,
115 t->last_frame->linesize[index], add);
116 }
117 }
118
idct_put(MadContext * t,AVFrame * frame,int16_t * block,int mb_x,int mb_y,int j)119 static inline void idct_put(MadContext *t, AVFrame *frame, int16_t *block,
120 int mb_x, int mb_y, int j)
121 {
122 if (j < 4) {
123 ff_ea_idct_put_c(
124 frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
125 frame->linesize[0], block);
126 } else if (!(t->avctx->flags & AV_CODEC_FLAG_GRAY)) {
127 int index = j - 3;
128 ff_ea_idct_put_c(
129 frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x*8,
130 frame->linesize[index], block);
131 }
132 }
133
decode_block_intra(MadContext * s,int16_t * block)134 static inline int decode_block_intra(MadContext *s, int16_t * block)
135 {
136 int level, i, j, run;
137 RLTable *rl = &ff_rl_mpeg1;
138 const uint8_t *scantable = s->scantable.permutated;
139 int16_t *quant_matrix = s->quant_matrix;
140
141 block[0] = (128 + get_sbits(&s->gb, 8)) * quant_matrix[0];
142
143 /* The RL decoder is derived from mpeg1_decode_block_intra;
144 Escaped level and run values a decoded differently */
145 i = 0;
146 {
147 OPEN_READER(re, &s->gb);
148 /* now quantify & encode AC coefficients */
149 for (;;) {
150 UPDATE_CACHE(re, &s->gb);
151 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
152
153 if (level == 127) {
154 break;
155 } else if (level != 0) {
156 i += run;
157 if (i > 63) {
158 av_log(s->avctx, AV_LOG_ERROR,
159 "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
160 return -1;
161 }
162 j = scantable[i];
163 level = (level*quant_matrix[j]) >> 4;
164 level = (level-1)|1;
165 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
166 LAST_SKIP_BITS(re, &s->gb, 1);
167 } else {
168 /* escape */
169 UPDATE_CACHE(re, &s->gb);
170 level = SHOW_SBITS(re, &s->gb, 10); SKIP_BITS(re, &s->gb, 10);
171
172 UPDATE_CACHE(re, &s->gb);
173 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
174
175 i += run;
176 if (i > 63) {
177 av_log(s->avctx, AV_LOG_ERROR,
178 "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
179 return -1;
180 }
181 j = scantable[i];
182 if (level < 0) {
183 level = -level;
184 level = (level*quant_matrix[j]) >> 4;
185 level = (level-1)|1;
186 level = -level;
187 } else {
188 level = (level*quant_matrix[j]) >> 4;
189 level = (level-1)|1;
190 }
191 }
192
193 block[j] = level;
194 }
195 CLOSE_READER(re, &s->gb);
196 }
197 return 0;
198 }
199
decode_motion(GetBitContext * gb)200 static int decode_motion(GetBitContext *gb)
201 {
202 int value = 0;
203 if (get_bits1(gb)) {
204 if (get_bits1(gb))
205 value = -17;
206 value += get_bits(gb, 4) + 1;
207 }
208 return value;
209 }
210
decode_mb(MadContext * s,AVFrame * frame,int inter)211 static int decode_mb(MadContext *s, AVFrame *frame, int inter)
212 {
213 int mv_map = 0;
214 int av_uninit(mv_x), av_uninit(mv_y);
215 int j;
216
217 if (inter) {
218 int v = decode210(&s->gb);
219 if (v < 2) {
220 mv_map = v ? get_bits(&s->gb, 6) : 63;
221 mv_x = decode_motion(&s->gb);
222 mv_y = decode_motion(&s->gb);
223 }
224 }
225
226 for (j=0; j<6; j++) {
227 if (mv_map & (1<<j)) { // mv_x and mv_y are guarded by mv_map
228 int add = 2*decode_motion(&s->gb);
229 if (s->last_frame->data[0])
230 comp_block(s, frame, s->mb_x, s->mb_y, j, mv_x, mv_y, add);
231 } else {
232 s->bdsp.clear_block(s->block);
233 if(decode_block_intra(s, s->block) < 0)
234 return -1;
235 idct_put(s, frame, s->block, s->mb_x, s->mb_y, j);
236 }
237 }
238 return 0;
239 }
240
calc_quant_matrix(MadContext * s,int qscale)241 static void calc_quant_matrix(MadContext *s, int qscale)
242 {
243 int i;
244
245 s->quant_matrix[0] = (ff_inv_aanscales[0]*ff_mpeg1_default_intra_matrix[0]) >> 11;
246 for (i=1; i<64; i++)
247 s->quant_matrix[i] = (ff_inv_aanscales[i]*ff_mpeg1_default_intra_matrix[i]*qscale + 32) >> 10;
248 }
249
decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame,AVPacket * avpkt)250 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
251 int *got_frame, AVPacket *avpkt)
252 {
253 const uint8_t *buf = avpkt->data;
254 int buf_size = avpkt->size;
255 MadContext *s = avctx->priv_data;
256 GetByteContext gb;
257 int width, height;
258 int chunk_type;
259 int inter, ret;
260
261 bytestream2_init(&gb, buf, buf_size);
262
263 chunk_type = bytestream2_get_le32(&gb);
264 inter = (chunk_type == MADm_TAG || chunk_type == MADe_TAG);
265 bytestream2_skip(&gb, 10);
266
267 av_reduce(&avctx->framerate.den, &avctx->framerate.num,
268 bytestream2_get_le16(&gb), 1000, 1<<30);
269
270 width = bytestream2_get_le16(&gb);
271 height = bytestream2_get_le16(&gb);
272 bytestream2_skip(&gb, 1);
273 calc_quant_matrix(s, bytestream2_get_byte(&gb));
274 bytestream2_skip(&gb, 2);
275
276 if (bytestream2_get_bytes_left(&gb) < 2) {
277 av_log(avctx, AV_LOG_ERROR, "Input data too small\n");
278 return AVERROR_INVALIDDATA;
279 }
280
281 if (width < 16 || height < 16) {
282 av_log(avctx, AV_LOG_ERROR, "Dimensions too small\n");
283 return AVERROR_INVALIDDATA;
284 }
285
286 if (avctx->width != width || avctx->height != height) {
287 av_frame_unref(s->last_frame);
288 if((width * (int64_t)height)/2048*7 > bytestream2_get_bytes_left(&gb))
289 return AVERROR_INVALIDDATA;
290 if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
291 return ret;
292 }
293
294 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
295 return ret;
296
297 if (inter && !s->last_frame->data[0]) {
298 av_log(avctx, AV_LOG_WARNING, "Missing reference frame.\n");
299 ret = ff_get_buffer(avctx, s->last_frame, AV_GET_BUFFER_FLAG_REF);
300 if (ret < 0)
301 return ret;
302 memset(s->last_frame->data[0], 0, s->last_frame->height *
303 s->last_frame->linesize[0]);
304 memset(s->last_frame->data[1], 0x80, s->last_frame->height / 2 *
305 s->last_frame->linesize[1]);
306 memset(s->last_frame->data[2], 0x80, s->last_frame->height / 2 *
307 s->last_frame->linesize[2]);
308 }
309
310 av_fast_padded_malloc(&s->bitstream_buf, &s->bitstream_buf_size,
311 bytestream2_get_bytes_left(&gb));
312 if (!s->bitstream_buf)
313 return AVERROR(ENOMEM);
314 s->bbdsp.bswap16_buf(s->bitstream_buf, (const uint16_t *)(buf + bytestream2_tell(&gb)),
315 bytestream2_get_bytes_left(&gb) / 2);
316 memset((uint8_t*)s->bitstream_buf + bytestream2_get_bytes_left(&gb), 0, AV_INPUT_BUFFER_PADDING_SIZE);
317 init_get_bits(&s->gb, s->bitstream_buf, 8*(bytestream2_get_bytes_left(&gb)));
318
319 for (s->mb_y=0; s->mb_y < (avctx->height+15)/16; s->mb_y++)
320 for (s->mb_x=0; s->mb_x < (avctx->width +15)/16; s->mb_x++)
321 if(decode_mb(s, frame, inter) < 0)
322 return AVERROR_INVALIDDATA;
323
324 *got_frame = 1;
325
326 if (chunk_type != MADe_TAG) {
327 av_frame_unref(s->last_frame);
328 if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
329 return ret;
330 }
331
332 return buf_size;
333 }
334
decode_end(AVCodecContext * avctx)335 static av_cold int decode_end(AVCodecContext *avctx)
336 {
337 MadContext *t = avctx->priv_data;
338 av_frame_free(&t->last_frame);
339 av_freep(&t->bitstream_buf);
340 return 0;
341 }
342
343 const FFCodec ff_eamad_decoder = {
344 .p.name = "eamad",
345 .p.long_name = NULL_IF_CONFIG_SMALL("Electronic Arts Madcow Video"),
346 .p.type = AVMEDIA_TYPE_VIDEO,
347 .p.id = AV_CODEC_ID_MAD,
348 .priv_data_size = sizeof(MadContext),
349 .init = decode_init,
350 .close = decode_end,
351 FF_CODEC_DECODE_CB(decode_frame),
352 .p.capabilities = AV_CODEC_CAP_DR1,
353 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
354 };
355