huffman: add a zero_count flag and use it in fraps
[libav.git] / libavcodec / fraps.c
1 /*
2 * Fraps FPS1 decoder
3 * Copyright (c) 2005 Roine Gustafsson
4 * Copyright (c) 2006 Konstantin Shishkov
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 /**
24 * @file fraps.c
25 * Lossless Fraps 'FPS1' decoder
26 * @author Roine Gustafsson <roine at users sf net>
27 * @author Konstantin Shishkov
28 *
29 * Codec algorithm for version 0 is taken from Transcode <www.transcoding.org>
30 *
31 * Version 2 files support by Konstantin Shishkov
32 */
33
34 #include "avcodec.h"
35 #include "bitstream.h"
36 #include "huffman.h"
37 #include "bytestream.h"
38 #include "dsputil.h"
39
40 #define FPS_TAG MKTAG('F', 'P', 'S', 'x')
41
42 /**
43 * local variable storage
44 */
45 typedef struct FrapsContext{
46 AVCodecContext *avctx;
47 AVFrame frame;
48 uint8_t *tmpbuf;
49 DSPContext dsp;
50 } FrapsContext;
51
52
53 /**
54 * initializes decoder
55 * @param avctx codec context
56 * @return 0 on success or negative if fails
57 */
58 static int decode_init(AVCodecContext *avctx)
59 {
60 FrapsContext * const s = avctx->priv_data;
61
62 avctx->coded_frame = (AVFrame*)&s->frame;
63 avctx->pix_fmt= PIX_FMT_NONE; /* set in decode_frame */
64
65 s->avctx = avctx;
66 s->frame.data[0] = NULL;
67 s->tmpbuf = NULL;
68
69 dsputil_init(&s->dsp, avctx);
70
71 return 0;
72 }
73
74 /**
75 * Comparator - our nodes should ascend by count
76 * but with preserved symbol order
77 */
78 static int huff_cmp(const void *va, const void *vb){
79 const Node *a = va, *b = vb;
80 return (a->count - b->count)*256 + a->sym - b->sym;
81 }
82
83 /**
84 * decode Fraps v2 packed plane
85 */
86 static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
87 int h, const uint8_t *src, int size, int Uoff)
88 {
89 int i, j;
90 GetBitContext gb;
91 VLC vlc;
92 Node nodes[512];
93
94 for(i = 0; i < 256; i++)
95 nodes[i].count = bytestream_get_le32(&src);
96 size -= 1024;
97 if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp,
98 FF_HUFFMAN_FLAG_ZERO_COUNT) < 0)
99 return -1;
100 /* we have built Huffman table and are ready to decode plane */
101
102 /* convert bits so they may be used by standard bitreader */
103 s->dsp.bswap_buf((uint32_t *)s->tmpbuf, (const uint32_t *)src, size >> 2);
104
105 init_get_bits(&gb, s->tmpbuf, size * 8);
106 for(j = 0; j < h; j++){
107 for(i = 0; i < w; i++){
108 dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
109 /* lines are stored as deltas between previous lines
110 * and we need to add 0x80 to the first lines of chroma planes
111 */
112 if(j) dst[i] += dst[i - stride];
113 else if(Uoff) dst[i] += 0x80;
114 }
115 dst += stride;
116 }
117 free_vlc(&vlc);
118 return 0;
119 }
120
121 /**
122 * decode a frame
123 * @param avctx codec context
124 * @param data output AVFrame
125 * @param data_size size of output data or 0 if no picture is returned
126 * @param buf input data frame
127 * @param buf_size size of input data frame
128 * @return number of consumed bytes on success or negative if decode fails
129 */
130 static int decode_frame(AVCodecContext *avctx,
131 void *data, int *data_size,
132 const uint8_t *buf, int buf_size)
133 {
134 FrapsContext * const s = avctx->priv_data;
135 AVFrame *frame = data;
136 AVFrame * const f = (AVFrame*)&s->frame;
137 uint32_t header;
138 unsigned int version,header_size;
139 unsigned int x, y;
140 const uint32_t *buf32;
141 uint32_t *luma1,*luma2,*cb,*cr;
142 uint32_t offs[4];
143 int i, is_chroma, planes;
144
145
146 header = AV_RL32(buf);
147 version = header & 0xff;
148 header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
149
150 if (version > 2 && version != 4) {
151 av_log(avctx, AV_LOG_ERROR,
152 "This file is encoded with Fraps version %d. " \
153 "This codec can only decode version 0, 1, 2 and 4.\n", version);
154 return -1;
155 }
156
157 buf+=4;
158 if (header_size == 8)
159 buf+=4;
160
161 switch(version) {
162 case 0:
163 default:
164 /* Fraps v0 is a reordered YUV420 */
165 avctx->pix_fmt = PIX_FMT_YUV420P;
166
167 if ( (buf_size != avctx->width*avctx->height*3/2+header_size) &&
168 (buf_size != header_size) ) {
169 av_log(avctx, AV_LOG_ERROR,
170 "Invalid frame length %d (should be %d)\n",
171 buf_size, avctx->width*avctx->height*3/2+header_size);
172 return -1;
173 }
174
175 if (( (avctx->width % 8) != 0) || ( (avctx->height % 2) != 0 )) {
176 av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
177 avctx->width, avctx->height);
178 return -1;
179 }
180
181 f->reference = 1;
182 f->buffer_hints = FF_BUFFER_HINTS_VALID |
183 FF_BUFFER_HINTS_PRESERVE |
184 FF_BUFFER_HINTS_REUSABLE;
185 if (avctx->reget_buffer(avctx, f)) {
186 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
187 return -1;
188 }
189 /* bit 31 means same as previous pic */
190 f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
191 f->key_frame = f->pict_type == FF_I_TYPE;
192
193 if (f->pict_type == FF_I_TYPE) {
194 buf32=(const uint32_t*)buf;
195 for(y=0; y<avctx->height/2; y++){
196 luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
197 luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
198 cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
199 cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
200 for(x=0; x<avctx->width; x+=8){
201 *(luma1++) = *(buf32++);
202 *(luma1++) = *(buf32++);
203 *(luma2++) = *(buf32++);
204 *(luma2++) = *(buf32++);
205 *(cr++) = *(buf32++);
206 *(cb++) = *(buf32++);
207 }
208 }
209 }
210 break;
211
212 case 1:
213 /* Fraps v1 is an upside-down BGR24 */
214 avctx->pix_fmt = PIX_FMT_BGR24;
215
216 if ( (buf_size != avctx->width*avctx->height*3+header_size) &&
217 (buf_size != header_size) ) {
218 av_log(avctx, AV_LOG_ERROR,
219 "Invalid frame length %d (should be %d)\n",
220 buf_size, avctx->width*avctx->height*3+header_size);
221 return -1;
222 }
223
224 f->reference = 1;
225 f->buffer_hints = FF_BUFFER_HINTS_VALID |
226 FF_BUFFER_HINTS_PRESERVE |
227 FF_BUFFER_HINTS_REUSABLE;
228 if (avctx->reget_buffer(avctx, f)) {
229 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
230 return -1;
231 }
232 /* bit 31 means same as previous pic */
233 f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
234 f->key_frame = f->pict_type == FF_I_TYPE;
235
236 if (f->pict_type == FF_I_TYPE) {
237 for(y=0; y<avctx->height; y++)
238 memcpy(&f->data[0][ (avctx->height-y)*f->linesize[0] ],
239 &buf[y*avctx->width*3],
240 f->linesize[0]);
241 }
242 break;
243
244 case 2:
245 case 4:
246 /**
247 * Fraps v2 is Huffman-coded YUV420 planes
248 * Fraps v4 is virtually the same
249 */
250 avctx->pix_fmt = PIX_FMT_YUV420P;
251 planes = 3;
252 f->reference = 1;
253 f->buffer_hints = FF_BUFFER_HINTS_VALID |
254 FF_BUFFER_HINTS_PRESERVE |
255 FF_BUFFER_HINTS_REUSABLE;
256 if (avctx->reget_buffer(avctx, f)) {
257 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
258 return -1;
259 }
260 /* skip frame */
261 if(buf_size == 8) {
262 f->pict_type = FF_P_TYPE;
263 f->key_frame = 0;
264 break;
265 }
266 f->pict_type = FF_I_TYPE;
267 f->key_frame = 1;
268 if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
269 av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
270 return -1;
271 }
272 for(i = 0; i < planes; i++) {
273 offs[i] = AV_RL32(buf + 4 + i * 4);
274 if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
275 av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
276 return -1;
277 }
278 }
279 offs[planes] = buf_size;
280 for(i = 0; i < planes; i++){
281 is_chroma = !!i;
282 s->tmpbuf = av_realloc(s->tmpbuf, offs[i + 1] - offs[i] - 1024 + FF_INPUT_BUFFER_PADDING_SIZE);
283 if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
284 avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma) < 0) {
285 av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
286 return -1;
287 }
288 }
289 break;
290 }
291
292 *frame = *f;
293 *data_size = sizeof(AVFrame);
294
295 return buf_size;
296 }
297
298
299 /**
300 * closes decoder
301 * @param avctx codec context
302 * @return 0 on success or negative if fails
303 */
304 static int decode_end(AVCodecContext *avctx)
305 {
306 FrapsContext *s = (FrapsContext*)avctx->priv_data;
307
308 if (s->frame.data[0])
309 avctx->release_buffer(avctx, &s->frame);
310
311 av_freep(&s->tmpbuf);
312 return 0;
313 }
314
315
316 AVCodec fraps_decoder = {
317 "fraps",
318 CODEC_TYPE_VIDEO,
319 CODEC_ID_FRAPS,
320 sizeof(FrapsContext),
321 decode_init,
322 NULL,
323 decode_end,
324 decode_frame,
325 CODEC_CAP_DR1,
326 };