7b7a386adc4684261fea60a87bc1dab446a18f52
[libav.git] / libavcodec / dxa.c
1 /*
2 * Feeble Files/ScummVM DXA decoder
3 * Copyright (c) 2007 Konstantin Shishkov
4 *
5 * This file is part of Libav.
6 *
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.
11 *
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.
16 *
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
20 */
21
22 /**
23 * @file
24 * DXA Video decoder
25 */
26
27 #include <stdio.h>
28 #include <stdlib.h>
29
30 #include "libavutil/intreadwrite.h"
31 #include "avcodec.h"
32
33 #include <zlib.h>
34
35 /*
36 * Decoder context
37 */
38 typedef struct DxaDecContext {
39 AVFrame pic, prev;
40
41 int dsize;
42 uint8_t *decomp_buf;
43 uint32_t pal[256];
44 } DxaDecContext;
45
46 static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
47 static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
48
49 static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, uint8_t *src, uint8_t *ref)
50 {
51 uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
52 int i, j, k;
53 int type, x, y, d, d2;
54 int stride = c->pic.linesize[0];
55 uint32_t mask;
56
57 code = src + 12;
58 data = code + ((avctx->width * avctx->height) >> 4);
59 mv = data + AV_RB32(src + 0);
60 msk = mv + AV_RB32(src + 4);
61
62 for(j = 0; j < avctx->height; j += 4){
63 for(i = 0; i < avctx->width; i += 4){
64 tmp = dst + i;
65 tmp2 = ref + i;
66 type = *code++;
67 switch(type){
68 case 4: // motion compensation
69 x = (*mv) >> 4; if(x & 8) x = 8 - x;
70 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
71 tmp2 += x + y*stride;
72 case 0: // skip
73 case 5: // skip in method 12
74 for(y = 0; y < 4; y++){
75 memcpy(tmp, tmp2, 4);
76 tmp += stride;
77 tmp2 += stride;
78 }
79 break;
80 case 1: // masked change
81 case 10: // masked change with only half of pixels changed
82 case 11: // cases 10-15 are for method 12 only
83 case 12:
84 case 13:
85 case 14:
86 case 15:
87 if(type == 1){
88 mask = AV_RB16(msk);
89 msk += 2;
90 }else{
91 type -= 10;
92 mask = ((msk[0] & 0xF0) << shift1[type]) | ((msk[0] & 0xF) << shift2[type]);
93 msk++;
94 }
95 for(y = 0; y < 4; y++){
96 for(x = 0; x < 4; x++){
97 tmp[x] = (mask & 0x8000) ? *data++ : tmp2[x];
98 mask <<= 1;
99 }
100 tmp += stride;
101 tmp2 += stride;
102 }
103 break;
104 case 2: // fill block
105 for(y = 0; y < 4; y++){
106 memset(tmp, data[0], 4);
107 tmp += stride;
108 }
109 data++;
110 break;
111 case 3: // raw block
112 for(y = 0; y < 4; y++){
113 memcpy(tmp, data, 4);
114 data += 4;
115 tmp += stride;
116 }
117 break;
118 case 8: // subblocks - method 13 only
119 mask = *msk++;
120 for(k = 0; k < 4; k++){
121 d = ((k & 1) << 1) + ((k & 2) * stride);
122 d2 = ((k & 1) << 1) + ((k & 2) * stride);
123 tmp2 = ref + i + d2;
124 switch(mask & 0xC0){
125 case 0x80: // motion compensation
126 x = (*mv) >> 4; if(x & 8) x = 8 - x;
127 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
128 tmp2 += x + y*stride;
129 case 0x00: // skip
130 tmp[d + 0 ] = tmp2[0];
131 tmp[d + 1 ] = tmp2[1];
132 tmp[d + 0 + stride] = tmp2[0 + stride];
133 tmp[d + 1 + stride] = tmp2[1 + stride];
134 break;
135 case 0x40: // fill
136 tmp[d + 0 ] = data[0];
137 tmp[d + 1 ] = data[0];
138 tmp[d + 0 + stride] = data[0];
139 tmp[d + 1 + stride] = data[0];
140 data++;
141 break;
142 case 0xC0: // raw
143 tmp[d + 0 ] = *data++;
144 tmp[d + 1 ] = *data++;
145 tmp[d + 0 + stride] = *data++;
146 tmp[d + 1 + stride] = *data++;
147 break;
148 }
149 mask <<= 2;
150 }
151 break;
152 case 32: // vector quantization - 2 colors
153 mask = AV_RB16(msk);
154 msk += 2;
155 for(y = 0; y < 4; y++){
156 for(x = 0; x < 4; x++){
157 tmp[x] = data[mask & 1];
158 mask >>= 1;
159 }
160 tmp += stride;
161 tmp2 += stride;
162 }
163 data += 2;
164 break;
165 case 33: // vector quantization - 3 or 4 colors
166 case 34:
167 mask = AV_RB32(msk);
168 msk += 4;
169 for(y = 0; y < 4; y++){
170 for(x = 0; x < 4; x++){
171 tmp[x] = data[mask & 3];
172 mask >>= 2;
173 }
174 tmp += stride;
175 tmp2 += stride;
176 }
177 data += type - 30;
178 break;
179 default:
180 av_log(avctx, AV_LOG_ERROR, "Unknown opcode %d\n", type);
181 return -1;
182 }
183 }
184 dst += stride * 4;
185 ref += stride * 4;
186 }
187 return 0;
188 }
189
190 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
191 {
192 const uint8_t *buf = avpkt->data;
193 int buf_size = avpkt->size;
194 DxaDecContext * const c = avctx->priv_data;
195 uint8_t *outptr, *srcptr, *tmpptr;
196 unsigned long dsize;
197 int i, j, compr;
198 int stride;
199 int orig_buf_size = buf_size;
200 int pc = 0;
201
202 /* make the palette available on the way out */
203 if(buf[0]=='C' && buf[1]=='M' && buf[2]=='A' && buf[3]=='P'){
204 int r, g, b;
205
206 buf += 4;
207 for(i = 0; i < 256; i++){
208 r = *buf++;
209 g = *buf++;
210 b = *buf++;
211 c->pal[i] = (r << 16) | (g << 8) | b;
212 }
213 pc = 1;
214 buf_size -= 768+4;
215 }
216
217 if(avctx->get_buffer(avctx, &c->pic) < 0){
218 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
219 return -1;
220 }
221 memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE);
222 c->pic.palette_has_changed = pc;
223
224 outptr = c->pic.data[0];
225 srcptr = c->decomp_buf;
226 tmpptr = c->prev.data[0];
227 stride = c->pic.linesize[0];
228
229 if(buf[0]=='N' && buf[1]=='U' && buf[2]=='L' && buf[3]=='L')
230 compr = -1;
231 else
232 compr = buf[4];
233
234 dsize = c->dsize;
235 if((compr != 4 && compr != -1) && uncompress(c->decomp_buf, &dsize, buf + 9, buf_size - 9) != Z_OK){
236 av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
237 return -1;
238 }
239 switch(compr){
240 case -1:
241 c->pic.key_frame = 0;
242 c->pic.pict_type = AV_PICTURE_TYPE_P;
243 if(c->prev.data[0])
244 memcpy(c->pic.data[0], c->prev.data[0], c->pic.linesize[0] * avctx->height);
245 else{ // Should happen only when first frame is 'NULL'
246 memset(c->pic.data[0], 0, c->pic.linesize[0] * avctx->height);
247 c->pic.key_frame = 1;
248 c->pic.pict_type = AV_PICTURE_TYPE_I;
249 }
250 break;
251 case 2:
252 case 3:
253 case 4:
254 case 5:
255 c->pic.key_frame = !(compr & 1);
256 c->pic.pict_type = (compr & 1) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
257 for(j = 0; j < avctx->height; j++){
258 if(compr & 1){
259 for(i = 0; i < avctx->width; i++)
260 outptr[i] = srcptr[i] ^ tmpptr[i];
261 tmpptr += stride;
262 }else
263 memcpy(outptr, srcptr, avctx->width);
264 outptr += stride;
265 srcptr += avctx->width;
266 }
267 break;
268 case 12: // ScummVM coding
269 case 13:
270 c->pic.key_frame = 0;
271 c->pic.pict_type = AV_PICTURE_TYPE_P;
272 decode_13(avctx, c, c->pic.data[0], srcptr, c->prev.data[0]);
273 break;
274 default:
275 av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", buf[4]);
276 return -1;
277 }
278
279 FFSWAP(AVFrame, c->pic, c->prev);
280 if(c->pic.data[0])
281 avctx->release_buffer(avctx, &c->pic);
282
283 *data_size = sizeof(AVFrame);
284 *(AVFrame*)data = c->prev;
285
286 /* always report that the buffer was completely consumed */
287 return orig_buf_size;
288 }
289
290 static av_cold int decode_init(AVCodecContext *avctx)
291 {
292 DxaDecContext * const c = avctx->priv_data;
293
294 avctx->pix_fmt = PIX_FMT_PAL8;
295
296 c->dsize = avctx->width * avctx->height * 2;
297 if((c->decomp_buf = av_malloc(c->dsize)) == NULL) {
298 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
299 return -1;
300 }
301
302 return 0;
303 }
304
305 static av_cold int decode_end(AVCodecContext *avctx)
306 {
307 DxaDecContext * const c = avctx->priv_data;
308
309 av_freep(&c->decomp_buf);
310 if(c->prev.data[0])
311 avctx->release_buffer(avctx, &c->prev);
312 if(c->pic.data[0])
313 avctx->release_buffer(avctx, &c->pic);
314
315 return 0;
316 }
317
318 AVCodec ff_dxa_decoder = {
319 .name = "dxa",
320 .type = AVMEDIA_TYPE_VIDEO,
321 .id = CODEC_ID_DXA,
322 .priv_data_size = sizeof(DxaDecContext),
323 .init = decode_init,
324 .close = decode_end,
325 .decode = decode_frame,
326 .capabilities = CODEC_CAP_DR1,
327 .long_name = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
328 };