Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / xxan.c
CommitLineData
2ba45a60
DM
1/*
2 * Wing Commander/Xan Video Decoder
3 * Copyright (C) 2011 Konstantin Shishkov
4 * based on work by Mike Melanson
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#include "avcodec.h"
24#include "libavutil/intreadwrite.h"
25#include "libavutil/mem.h"
26#include "bytestream.h"
27#define BITSTREAM_READER_LE
28#include "get_bits.h"
29#include "internal.h"
30
31typedef struct XanContext {
32 AVCodecContext *avctx;
33 AVFrame *pic;
34
35 uint8_t *y_buffer;
36 uint8_t *scratch_buffer;
37 int buffer_size;
38 GetByteContext gb;
39} XanContext;
40
41static av_cold int xan_decode_end(AVCodecContext *avctx)
42{
43 XanContext *s = avctx->priv_data;
44
45 av_frame_free(&s->pic);
46
47 av_freep(&s->y_buffer);
48 av_freep(&s->scratch_buffer);
49
50 return 0;
51}
52
53static av_cold int xan_decode_init(AVCodecContext *avctx)
54{
55 XanContext *s = avctx->priv_data;
56
57 s->avctx = avctx;
58
59 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
60
61 if (avctx->height < 8) {
62 av_log(avctx, AV_LOG_ERROR, "Invalid frame height: %d.\n", avctx->height);
63 return AVERROR(EINVAL);
64 }
65 if (avctx->width & 1) {
66 av_log(avctx, AV_LOG_ERROR, "Invalid frame width: %d.\n", avctx->width);
67 return AVERROR(EINVAL);
68 }
69
70 s->buffer_size = avctx->width * avctx->height;
71 s->y_buffer = av_malloc(s->buffer_size);
72 if (!s->y_buffer)
73 return AVERROR(ENOMEM);
74 s->scratch_buffer = av_malloc(s->buffer_size + 130);
75 if (!s->scratch_buffer) {
76 xan_decode_end(avctx);
77 return AVERROR(ENOMEM);
78 }
79
80 s->pic = av_frame_alloc();
81 if (!s->pic) {
82 xan_decode_end(avctx);
83 return AVERROR(ENOMEM);
84 }
85
86 return 0;
87}
88
89static int xan_unpack_luma(XanContext *s,
90 uint8_t *dst, const int dst_size)
91{
92 int tree_size, eof;
93 int bits, mask;
94 int tree_root, node;
95 const uint8_t *dst_end = dst + dst_size;
96 GetByteContext tree = s->gb;
97 int start_off = bytestream2_tell(&tree);
98
99 tree_size = bytestream2_get_byte(&s->gb);
100 eof = bytestream2_get_byte(&s->gb);
101 tree_root = eof + tree_size;
102 bytestream2_skip(&s->gb, tree_size * 2);
103
104 node = tree_root;
105 bits = bytestream2_get_byte(&s->gb);
106 mask = 0x80;
107 for (;;) {
108 int bit = !!(bits & mask);
109 mask >>= 1;
110 bytestream2_seek(&tree, start_off + node*2 + bit - eof * 2, SEEK_SET);
111 node = bytestream2_get_byte(&tree);
112 if (node == eof)
113 break;
114 if (node < eof) {
115 *dst++ = node;
116 if (dst > dst_end)
117 break;
118 node = tree_root;
119 }
120 if (!mask) {
121 if (bytestream2_get_bytes_left(&s->gb) <= 0)
122 break;
123 bits = bytestream2_get_byteu(&s->gb);
124 mask = 0x80;
125 }
126 }
127 return dst != dst_end ? AVERROR_INVALIDDATA : 0;
128}
129
130/* almost the same as in xan_wc3 decoder */
131static int xan_unpack(XanContext *s,
132 uint8_t *dest, const int dest_len)
133{
134 uint8_t opcode;
135 int size;
136 uint8_t *orig_dest = dest;
137 const uint8_t *dest_end = dest + dest_len;
138
139 while (dest < dest_end) {
140 if (bytestream2_get_bytes_left(&s->gb) <= 0)
141 return AVERROR_INVALIDDATA;
142
143 opcode = bytestream2_get_byteu(&s->gb);
144
145 if (opcode < 0xe0) {
146 int size2, back;
147 if ((opcode & 0x80) == 0) {
148 size = opcode & 3;
149 back = ((opcode & 0x60) << 3) + bytestream2_get_byte(&s->gb) + 1;
150 size2 = ((opcode & 0x1c) >> 2) + 3;
151 } else if ((opcode & 0x40) == 0) {
152 size = bytestream2_peek_byte(&s->gb) >> 6;
153 back = (bytestream2_get_be16(&s->gb) & 0x3fff) + 1;
154 size2 = (opcode & 0x3f) + 4;
155 } else {
156 size = opcode & 3;
157 back = ((opcode & 0x10) << 12) + bytestream2_get_be16(&s->gb) + 1;
158 size2 = ((opcode & 0x0c) << 6) + bytestream2_get_byte(&s->gb) + 5;
159 if (size + size2 > dest_end - dest)
160 break;
161 }
162 if (dest + size + size2 > dest_end ||
163 dest - orig_dest + size < back)
164 return AVERROR_INVALIDDATA;
165 bytestream2_get_buffer(&s->gb, dest, size);
166 dest += size;
167 av_memcpy_backptr(dest, back, size2);
168 dest += size2;
169 } else {
170 int finish = opcode >= 0xfc;
171
172 size = finish ? opcode & 3 : ((opcode & 0x1f) << 2) + 4;
173 if (dest_end - dest < size)
174 return AVERROR_INVALIDDATA;
175 bytestream2_get_buffer(&s->gb, dest, size);
176 dest += size;
177 if (finish)
178 break;
179 }
180 }
181 return dest - orig_dest;
182}
183
184static int xan_decode_chroma(AVCodecContext *avctx, unsigned chroma_off)
185{
186 XanContext *s = avctx->priv_data;
187 uint8_t *U, *V;
188 int val, uval, vval;
189 int i, j;
190 const uint8_t *src, *src_end;
191 const uint8_t *table;
192 int mode, offset, dec_size, table_size;
193
194 if (!chroma_off)
195 return 0;
196 if (chroma_off + 4 >= bytestream2_get_bytes_left(&s->gb)) {
197 av_log(avctx, AV_LOG_ERROR, "Invalid chroma block position\n");
198 return AVERROR_INVALIDDATA;
199 }
200 bytestream2_seek(&s->gb, chroma_off + 4, SEEK_SET);
201 mode = bytestream2_get_le16(&s->gb);
202 table = s->gb.buffer;
203 table_size = bytestream2_get_le16(&s->gb);
204 offset = table_size * 2;
205 table_size += 1;
206
207 if (offset >= bytestream2_get_bytes_left(&s->gb)) {
208 av_log(avctx, AV_LOG_ERROR, "Invalid chroma block offset\n");
209 return AVERROR_INVALIDDATA;
210 }
211
212 bytestream2_skip(&s->gb, offset);
213 memset(s->scratch_buffer, 0, s->buffer_size);
214 dec_size = xan_unpack(s, s->scratch_buffer, s->buffer_size);
215 if (dec_size < 0) {
216 av_log(avctx, AV_LOG_ERROR, "Chroma unpacking failed\n");
217 return dec_size;
218 }
219
220 U = s->pic->data[1];
221 V = s->pic->data[2];
222 src = s->scratch_buffer;
223 src_end = src + dec_size;
224 if (mode) {
225 for (j = 0; j < avctx->height >> 1; j++) {
226 for (i = 0; i < avctx->width >> 1; i++) {
227 if (src_end - src < 1)
228 return 0;
229 val = *src++;
230 if (val) {
231 if (val >= table_size)
232 return AVERROR_INVALIDDATA;
233 val = AV_RL16(table + (val << 1));
234 uval = (val >> 3) & 0xF8;
235 vval = (val >> 8) & 0xF8;
236 U[i] = uval | (uval >> 5);
237 V[i] = vval | (vval >> 5);
238 }
239 }
240 U += s->pic->linesize[1];
241 V += s->pic->linesize[2];
242 }
243 if (avctx->height & 1) {
244 memcpy(U, U - s->pic->linesize[1], avctx->width >> 1);
245 memcpy(V, V - s->pic->linesize[2], avctx->width >> 1);
246 }
247 } else {
248 uint8_t *U2 = U + s->pic->linesize[1];
249 uint8_t *V2 = V + s->pic->linesize[2];
250
251 for (j = 0; j < avctx->height >> 2; j++) {
252 for (i = 0; i < avctx->width >> 1; i += 2) {
253 if (src_end - src < 1)
254 return 0;
255 val = *src++;
256 if (val) {
257 if (val >= table_size)
258 return AVERROR_INVALIDDATA;
259 val = AV_RL16(table + (val << 1));
260 uval = (val >> 3) & 0xF8;
261 vval = (val >> 8) & 0xF8;
262 U[i] = U[i+1] = U2[i] = U2[i+1] = uval | (uval >> 5);
263 V[i] = V[i+1] = V2[i] = V2[i+1] = vval | (vval >> 5);
264 }
265 }
266 U += s->pic->linesize[1] * 2;
267 V += s->pic->linesize[2] * 2;
268 U2 += s->pic->linesize[1] * 2;
269 V2 += s->pic->linesize[2] * 2;
270 }
271 if (avctx->height & 3) {
272 int lines = ((avctx->height + 1) >> 1) - (avctx->height >> 2) * 2;
273
274 memcpy(U, U - lines * s->pic->linesize[1], lines * s->pic->linesize[1]);
275 memcpy(V, V - lines * s->pic->linesize[2], lines * s->pic->linesize[2]);
276 }
277 }
278
279 return 0;
280}
281
282static int xan_decode_frame_type0(AVCodecContext *avctx)
283{
284 XanContext *s = avctx->priv_data;
285 uint8_t *ybuf, *prev_buf, *src = s->scratch_buffer;
286 unsigned chroma_off, corr_off;
287 int cur, last;
288 int i, j;
289 int ret;
290
291 chroma_off = bytestream2_get_le32(&s->gb);
292 corr_off = bytestream2_get_le32(&s->gb);
293
294 if ((ret = xan_decode_chroma(avctx, chroma_off)) != 0)
295 return ret;
296
297 if (corr_off >= bytestream2_size(&s->gb)) {
298 av_log(avctx, AV_LOG_WARNING, "Ignoring invalid correction block position\n");
299 corr_off = 0;
300 }
301 bytestream2_seek(&s->gb, 12, SEEK_SET);
302 ret = xan_unpack_luma(s, src, s->buffer_size >> 1);
303 if (ret) {
304 av_log(avctx, AV_LOG_ERROR, "Luma decoding failed\n");
305 return ret;
306 }
307
308 ybuf = s->y_buffer;
309 last = *src++;
310 ybuf[0] = last << 1;
311 for (j = 1; j < avctx->width - 1; j += 2) {
312 cur = (last + *src++) & 0x1F;
313 ybuf[j] = last + cur;
314 ybuf[j+1] = cur << 1;
315 last = cur;
316 }
317 ybuf[j] = last << 1;
318 prev_buf = ybuf;
319 ybuf += avctx->width;
320
321 for (i = 1; i < avctx->height; i++) {
322 last = ((prev_buf[0] >> 1) + *src++) & 0x1F;
323 ybuf[0] = last << 1;
324 for (j = 1; j < avctx->width - 1; j += 2) {
325 cur = ((prev_buf[j + 1] >> 1) + *src++) & 0x1F;
326 ybuf[j] = last + cur;
327 ybuf[j+1] = cur << 1;
328 last = cur;
329 }
330 ybuf[j] = last << 1;
331 prev_buf = ybuf;
332 ybuf += avctx->width;
333 }
334
335 if (corr_off) {
336 int dec_size;
337
338 bytestream2_seek(&s->gb, 8 + corr_off, SEEK_SET);
339 dec_size = xan_unpack(s, s->scratch_buffer, s->buffer_size / 2);
340 if (dec_size < 0)
341 dec_size = 0;
342 else
343 dec_size = FFMIN(dec_size, s->buffer_size/2 - 1);
344
345 for (i = 0; i < dec_size; i++)
346 s->y_buffer[i*2+1] = (s->y_buffer[i*2+1] + (s->scratch_buffer[i] << 1)) & 0x3F;
347 }
348
349 src = s->y_buffer;
350 ybuf = s->pic->data[0];
351 for (j = 0; j < avctx->height; j++) {
352 for (i = 0; i < avctx->width; i++)
353 ybuf[i] = (src[i] << 2) | (src[i] >> 3);
354 src += avctx->width;
355 ybuf += s->pic->linesize[0];
356 }
357
358 return 0;
359}
360
361static int xan_decode_frame_type1(AVCodecContext *avctx)
362{
363 XanContext *s = avctx->priv_data;
364 uint8_t *ybuf, *src = s->scratch_buffer;
365 int cur, last;
366 int i, j;
367 int ret;
368
369 if ((ret = xan_decode_chroma(avctx, bytestream2_get_le32(&s->gb))) != 0)
370 return ret;
371
372 bytestream2_seek(&s->gb, 16, SEEK_SET);
373 ret = xan_unpack_luma(s, src,
374 s->buffer_size >> 1);
375 if (ret) {
376 av_log(avctx, AV_LOG_ERROR, "Luma decoding failed\n");
377 return ret;
378 }
379
380 ybuf = s->y_buffer;
381 for (i = 0; i < avctx->height; i++) {
382 last = (ybuf[0] + (*src++ << 1)) & 0x3F;
383 ybuf[0] = last;
384 for (j = 1; j < avctx->width - 1; j += 2) {
385 cur = (ybuf[j + 1] + (*src++ << 1)) & 0x3F;
386 ybuf[j] = (last + cur) >> 1;
387 ybuf[j+1] = cur;
388 last = cur;
389 }
390 ybuf[j] = last;
391 ybuf += avctx->width;
392 }
393
394 src = s->y_buffer;
395 ybuf = s->pic->data[0];
396 for (j = 0; j < avctx->height; j++) {
397 for (i = 0; i < avctx->width; i++)
398 ybuf[i] = (src[i] << 2) | (src[i] >> 3);
399 src += avctx->width;
400 ybuf += s->pic->linesize[0];
401 }
402
403 return 0;
404}
405
406static int xan_decode_frame(AVCodecContext *avctx,
407 void *data, int *got_frame,
408 AVPacket *avpkt)
409{
410 XanContext *s = avctx->priv_data;
411 int ftype;
412 int ret;
413
414 if ((ret = ff_reget_buffer(avctx, s->pic)) < 0)
415 return ret;
416
417 bytestream2_init(&s->gb, avpkt->data, avpkt->size);
418 ftype = bytestream2_get_le32(&s->gb);
419 switch (ftype) {
420 case 0:
421 ret = xan_decode_frame_type0(avctx);
422 break;
423 case 1:
424 ret = xan_decode_frame_type1(avctx);
425 break;
426 default:
427 av_log(avctx, AV_LOG_ERROR, "Unknown frame type %d\n", ftype);
428 return AVERROR_INVALIDDATA;
429 }
430 if (ret)
431 return ret;
432
433 if ((ret = av_frame_ref(data, s->pic)) < 0)
434 return ret;
435
436 *got_frame = 1;
437
438 return avpkt->size;
439}
440
441AVCodec ff_xan_wc4_decoder = {
442 .name = "xan_wc4",
443 .long_name = NULL_IF_CONFIG_SMALL("Wing Commander IV / Xxan"),
444 .type = AVMEDIA_TYPE_VIDEO,
445 .id = AV_CODEC_ID_XAN_WC4,
446 .priv_data_size = sizeof(XanContext),
447 .init = xan_decode_init,
448 .close = xan_decode_end,
449 .decode = xan_decode_frame,
450 .capabilities = CODEC_CAP_DR1,
451};