1 /*
2 * Feeble Files/ScummVM DXA decoder
3 * Copyright (c) 2007 Konstantin Shishkov
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 Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * DXA Video decoder
25 */
26
27 #include <stdio.h>
28 #include <stdlib.h>
29
30 #include "libavutil/common.h"
31 #include "libavutil/intreadwrite.h"
32 #include "bytestream.h"
33 #include "avcodec.h"
34 #include "internal.h"
35
36 #include <zlib.h>
37
38 /*
39 * Decoder context
40 */
41 typedef struct DxaDecContext {
42 AVFrame *prev;
43
44 int dsize;
45 #define DECOMP_BUF_PADDING 16
46 uint8_t *decomp_buf;
47 uint32_t pal[256];
48 } DxaDecContext;
49
50 static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
51 static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
52
decode_13(AVCodecContext * avctx,DxaDecContext * c,uint8_t * dst,int stride,uint8_t * src,int srcsize,uint8_t * ref)53 static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
54 int stride, uint8_t *src, int srcsize, uint8_t *ref)
55 {
56 uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
57 uint8_t *src_end = src + srcsize;
58 int i, j, k;
59 int type, x, y, d, d2;
60 uint32_t mask;
61
62 if (12ULL + ((avctx->width * avctx->height) >> 4) + AV_RB32(src + 0) + AV_RB32(src + 4) > srcsize)
63 return AVERROR_INVALIDDATA;
64
65 code = src + 12;
66 data = code + ((avctx->width * avctx->height) >> 4);
67 mv = data + AV_RB32(src + 0);
68 msk = mv + AV_RB32(src + 4);
69
70 for(j = 0; j < avctx->height; j += 4){
71 for(i = 0; i < avctx->width; i += 4){
72 if (data > src_end || mv > src_end || msk > src_end)
73 return AVERROR_INVALIDDATA;
74 tmp = dst + i;
75 tmp2 = ref + i;
76 type = *code++;
77 switch(type){
78 case 4: // motion compensation
79 x = (*mv) >> 4; if(x & 8) x = 8 - x;
80 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
81 if (i < -x || avctx->width - i - 4 < x ||
82 j < -y || avctx->height - j - 4 < y) {
83 av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y);
84 return AVERROR_INVALIDDATA;
85 }
86 tmp2 += x + y*stride;
87 case 0: // skip
88 case 5: // skip in method 12
89 for(y = 0; y < 4; y++){
90 memcpy(tmp, tmp2, 4);
91 tmp += stride;
92 tmp2 += stride;
93 }
94 break;
95 case 1: // masked change
96 case 10: // masked change with only half of pixels changed
97 case 11: // cases 10-15 are for method 12 only
98 case 12:
99 case 13:
100 case 14:
101 case 15:
102 if(type == 1){
103 mask = AV_RB16(msk);
104 msk += 2;
105 }else{
106 type -= 10;
107 mask = ((msk[0] & 0xF0) << shift1[type]) | ((msk[0] & 0xF) << shift2[type]);
108 msk++;
109 }
110 for(y = 0; y < 4; y++){
111 for(x = 0; x < 4; x++){
112 tmp[x] = (mask & 0x8000) ? *data++ : tmp2[x];
113 mask <<= 1;
114 }
115 tmp += stride;
116 tmp2 += stride;
117 }
118 break;
119 case 2: // fill block
120 for(y = 0; y < 4; y++){
121 memset(tmp, data[0], 4);
122 tmp += stride;
123 }
124 data++;
125 break;
126 case 3: // raw block
127 for(y = 0; y < 4; y++){
128 memcpy(tmp, data, 4);
129 data += 4;
130 tmp += stride;
131 }
132 break;
133 case 8: // subblocks - method 13 only
134 mask = *msk++;
135 for(k = 0; k < 4; k++){
136 d = ((k & 1) << 1) + ((k & 2) * stride);
137 d2 = ((k & 1) << 1) + ((k & 2) * stride);
138 tmp2 = ref + i + d2;
139 switch(mask & 0xC0){
140 case 0x80: // motion compensation
141 x = (*mv) >> 4; if(x & 8) x = 8 - x;
142 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
143 if (i + 2*(k & 1) < -x || avctx->width - i - 2*(k & 1) - 2 < x ||
144 j + (k & 2) < -y || avctx->height - j - (k & 2) - 2 < y) {
145 av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y);
146 return AVERROR_INVALIDDATA;
147 }
148 tmp2 += x + y*stride;
149 case 0x00: // skip
150 tmp[d + 0 ] = tmp2[0];
151 tmp[d + 1 ] = tmp2[1];
152 tmp[d + 0 + stride] = tmp2[0 + stride];
153 tmp[d + 1 + stride] = tmp2[1 + stride];
154 break;
155 case 0x40: // fill
156 tmp[d + 0 ] = data[0];
157 tmp[d + 1 ] = data[0];
158 tmp[d + 0 + stride] = data[0];
159 tmp[d + 1 + stride] = data[0];
160 data++;
161 break;
162 case 0xC0: // raw
163 tmp[d + 0 ] = *data++;
164 tmp[d + 1 ] = *data++;
165 tmp[d + 0 + stride] = *data++;
166 tmp[d + 1 + stride] = *data++;
167 break;
168 }
169 mask <<= 2;
170 }
171 break;
172 case 32: // vector quantization - 2 colors
173 mask = AV_RB16(msk);
174 msk += 2;
175 for(y = 0; y < 4; y++){
176 for(x = 0; x < 4; x++){
177 tmp[x] = data[mask & 1];
178 mask >>= 1;
179 }
180 tmp += stride;
181 tmp2 += stride;
182 }
183 data += 2;
184 break;
185 case 33: // vector quantization - 3 or 4 colors
186 case 34:
187 mask = AV_RB32(msk);
188 msk += 4;
189 for(y = 0; y < 4; y++){
190 for(x = 0; x < 4; x++){
191 tmp[x] = data[mask & 3];
192 mask >>= 2;
193 }
194 tmp += stride;
195 tmp2 += stride;
196 }
197 data += type - 30;
198 break;
199 default:
200 av_log(avctx, AV_LOG_ERROR, "Unknown opcode %d\n", type);
201 return AVERROR_INVALIDDATA;
202 }
203 }
204 dst += stride * 4;
205 ref += stride * 4;
206 }
207 return 0;
208 }
209
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)210 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
211 {
212 AVFrame *frame = data;
213 DxaDecContext * const c = avctx->priv_data;
214 uint8_t *outptr, *srcptr, *tmpptr;
215 unsigned long dsize;
216 int i, j, compr, ret;
217 int stride;
218 int pc = 0;
219 GetByteContext gb;
220
221 bytestream2_init(&gb, avpkt->data, avpkt->size);
222
223 /* make the palette available on the way out */
224 if (bytestream2_peek_le32(&gb) == MKTAG('C','M','A','P')) {
225 bytestream2_skip(&gb, 4);
226 for(i = 0; i < 256; i++){
227 c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&gb);
228 }
229 pc = 1;
230 }
231
232 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
233 return ret;
234 memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
235 frame->palette_has_changed = pc;
236
237 outptr = frame->data[0];
238 srcptr = c->decomp_buf;
239 tmpptr = c->prev->data[0];
240 stride = frame->linesize[0];
241
242 if (bytestream2_get_le32(&gb) == MKTAG('N','U','L','L'))
243 compr = -1;
244 else
245 compr = bytestream2_get_byte(&gb);
246
247 dsize = c->dsize;
248 if (compr != 4 && compr != -1) {
249 bytestream2_skip(&gb, 4);
250 if (uncompress(c->decomp_buf, &dsize, avpkt->data + bytestream2_tell(&gb),
251 bytestream2_get_bytes_left(&gb)) != Z_OK) {
252 av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
253 return AVERROR_UNKNOWN;
254 }
255 memset(c->decomp_buf + dsize, 0, DECOMP_BUF_PADDING);
256 }
257
258 if (avctx->debug & FF_DEBUG_PICT_INFO)
259 av_log(avctx, AV_LOG_DEBUG, "compr:%2d, dsize:%d\n", compr, (int)dsize);
260
261 switch(compr){
262 case -1:
263 frame->key_frame = 0;
264 frame->pict_type = AV_PICTURE_TYPE_P;
265 if (c->prev->data[0])
266 memcpy(frame->data[0], c->prev->data[0], frame->linesize[0] * avctx->height);
267 else{ // Should happen only when first frame is 'NULL'
268 memset(frame->data[0], 0, frame->linesize[0] * avctx->height);
269 frame->key_frame = 1;
270 frame->pict_type = AV_PICTURE_TYPE_I;
271 }
272 break;
273 case 2:
274 case 4:
275 frame->key_frame = 1;
276 frame->pict_type = AV_PICTURE_TYPE_I;
277 for (j = 0; j < avctx->height; j++) {
278 memcpy(outptr, srcptr, avctx->width);
279 outptr += stride;
280 srcptr += avctx->width;
281 }
282 break;
283 case 3:
284 case 5:
285 if (!tmpptr) {
286 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
287 if (!(avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
288 return AVERROR_INVALIDDATA;
289 }
290 frame->key_frame = 0;
291 frame->pict_type = AV_PICTURE_TYPE_P;
292 for (j = 0; j < avctx->height; j++) {
293 if(tmpptr){
294 for(i = 0; i < avctx->width; i++)
295 outptr[i] = srcptr[i] ^ tmpptr[i];
296 tmpptr += stride;
297 }else
298 memcpy(outptr, srcptr, avctx->width);
299 outptr += stride;
300 srcptr += avctx->width;
301 }
302 break;
303 case 12: // ScummVM coding
304 case 13:
305 frame->key_frame = 0;
306 frame->pict_type = AV_PICTURE_TYPE_P;
307 if (!c->prev->data[0]) {
308 av_log(avctx, AV_LOG_ERROR, "Missing reference frame\n");
309 return AVERROR_INVALIDDATA;
310 }
311 decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, dsize, c->prev->data[0]);
312 break;
313 default:
314 av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", compr);
315 return AVERROR_INVALIDDATA;
316 }
317
318 av_frame_unref(c->prev);
319 if ((ret = av_frame_ref(c->prev, frame)) < 0)
320 return ret;
321
322 *got_frame = 1;
323
324 /* always report that the buffer was completely consumed */
325 return avpkt->size;
326 }
327
decode_init(AVCodecContext * avctx)328 static av_cold int decode_init(AVCodecContext *avctx)
329 {
330 DxaDecContext * const c = avctx->priv_data;
331
332 if (avctx->width%4 || avctx->height%4) {
333 avpriv_request_sample(avctx, "dimensions are not a multiple of 4");
334 return AVERROR_INVALIDDATA;
335 }
336
337 c->prev = av_frame_alloc();
338 if (!c->prev)
339 return AVERROR(ENOMEM);
340
341 avctx->pix_fmt = AV_PIX_FMT_PAL8;
342
343 c->dsize = avctx->width * avctx->height * 2;
344 c->decomp_buf = av_malloc(c->dsize + DECOMP_BUF_PADDING);
345 if (!c->decomp_buf) {
346 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
347 return AVERROR(ENOMEM);
348 }
349
350 return 0;
351 }
352
decode_end(AVCodecContext * avctx)353 static av_cold int decode_end(AVCodecContext *avctx)
354 {
355 DxaDecContext * const c = avctx->priv_data;
356
357 av_freep(&c->decomp_buf);
358 av_frame_free(&c->prev);
359
360 return 0;
361 }
362
363 AVCodec ff_dxa_decoder = {
364 .name = "dxa",
365 .long_name = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
366 .type = AVMEDIA_TYPE_VIDEO,
367 .id = AV_CODEC_ID_DXA,
368 .priv_data_size = sizeof(DxaDecContext),
369 .init = decode_init,
370 .close = decode_end,
371 .decode = decode_frame,
372 .capabilities = AV_CODEC_CAP_DR1,
373 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
374 };
375