6081c72c301c8d45d78de4de323e1a563e8ca915
[libav.git] / libavcodec / tscc2.c
1 /*
2 * TechSmith Screen Codec 2 (aka Dora) decoder
3 * Copyright (c) 2012 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 * TechSmith Screen Codec 2 decoder
25 */
26
27 #include <inttypes.h>
28
29 #define BITSTREAM_READER_LE
30 #include "avcodec.h"
31 #include "bitstream.h"
32 #include "bytestream.h"
33 #include "internal.h"
34 #include "mathops.h"
35 #include "tscc2data.h"
36
37 typedef struct TSCC2Context {
38 AVCodecContext *avctx;
39 AVFrame *pic;
40 int mb_width, mb_height;
41 uint8_t *slice_quants;
42 int quant[2];
43 int q[2][3];
44 BitstreamContext bc;
45
46 VLC dc_vlc, nc_vlc[NUM_VLC_SETS], ac_vlc[NUM_VLC_SETS];
47 int block[16];
48 } TSCC2Context;
49
50 static av_cold void free_vlcs(TSCC2Context *c)
51 {
52 int i;
53
54 ff_free_vlc(&c->dc_vlc);
55 for (i = 0; i < NUM_VLC_SETS; i++) {
56 ff_free_vlc(c->nc_vlc + i);
57 ff_free_vlc(c->ac_vlc + i);
58 }
59 }
60
61 static av_cold int init_vlcs(TSCC2Context *c)
62 {
63 int i, ret;
64
65 ret = ff_init_vlc_sparse(&c->dc_vlc, 9, DC_VLC_COUNT,
66 tscc2_dc_vlc_bits, 1, 1,
67 tscc2_dc_vlc_codes, 2, 2,
68 tscc2_dc_vlc_syms, 2, 2, INIT_VLC_LE);
69 if (ret)
70 return ret;
71
72 for (i = 0; i < NUM_VLC_SETS; i++) {
73 ret = ff_init_vlc_sparse(c->nc_vlc + i, 9, 16,
74 tscc2_nc_vlc_bits[i], 1, 1,
75 tscc2_nc_vlc_codes[i], 2, 2,
76 tscc2_nc_vlc_syms, 1, 1, INIT_VLC_LE);
77 if (ret) {
78 free_vlcs(c);
79 return ret;
80 }
81 ret = ff_init_vlc_sparse(c->ac_vlc + i, 9, tscc2_ac_vlc_sizes[i],
82 tscc2_ac_vlc_bits[i], 1, 1,
83 tscc2_ac_vlc_codes[i], 2, 2,
84 tscc2_ac_vlc_syms[i], 2, 2, INIT_VLC_LE);
85 if (ret) {
86 free_vlcs(c);
87 return ret;
88 }
89 }
90
91 return 0;
92 }
93
94 #define DEQUANT(val, q) ((q * val + 0x80) >> 8)
95 #define DCT1D(d0, d1, d2, d3, s0, s1, s2, s3, OP) \
96 OP(d0, 5 * ((s0) + (s1) + (s2)) + 2 * (s3)); \
97 OP(d1, 5 * ((s0) - (s2) - (s3)) + 2 * (s1)); \
98 OP(d2, 5 * ((s0) - (s2) + (s3)) - 2 * (s1)); \
99 OP(d3, 5 * ((s0) - (s1) + (s2)) - 2 * (s3)); \
100
101 #define COL_OP(a, b) a = b
102 #define ROW_OP(a, b) a = ((b) + 0x20) >> 6
103
104 static void tscc2_idct4_put(int *in, int q[3], uint8_t *dst, int stride)
105 {
106 int i;
107 int tblk[4 * 4];
108 int t0, t1, t2, t3;
109
110 for (i = 0; i < 4; i++) {
111 t0 = DEQUANT(q[0 + (i & 1)], in[0 * 4 + i]);
112 t1 = DEQUANT(q[1 + (i & 1)], in[1 * 4 + i]);
113 t2 = DEQUANT(q[0 + (i & 1)], in[2 * 4 + i]);
114 t3 = DEQUANT(q[1 + (i & 1)], in[3 * 4 + i]);
115 DCT1D(tblk[0 * 4 + i], tblk[1 * 4 + i],
116 tblk[2 * 4 + i], tblk[3 * 4 + i],
117 t0, t1, t2, t3, COL_OP);
118 }
119 for (i = 0; i < 4; i++) {
120 DCT1D(dst[0], dst[1], dst[2], dst[3],
121 tblk[i * 4 + 0], tblk[i * 4 + 1],
122 tblk[i * 4 + 2], tblk[i * 4 + 3], ROW_OP);
123 dst += stride;
124 }
125 }
126
127 static int tscc2_decode_mb(TSCC2Context *c, int *q, int vlc_set,
128 uint8_t *dst, int stride, int plane)
129 {
130 BitstreamContext *bc = &c->bc;
131 int prev_dc, dc, nc, ac, bpos, val;
132 int i, j, k, l;
133
134 if (bitstream_read_bit(bc)) {
135 if (bitstream_read_bit(bc)) {
136 val = bitstream_read(bc, 8);
137 for (i = 0; i < 8; i++, dst += stride)
138 memset(dst, val, 16);
139 } else {
140 if (bitstream_bits_left(bc) < 16 * 8 * 8)
141 return AVERROR_INVALIDDATA;
142 for (i = 0; i < 8; i++) {
143 for (j = 0; j < 16; j++)
144 dst[j] = bitstream_read(bc, 8);
145 dst += stride;
146 }
147 }
148 return 0;
149 }
150
151 prev_dc = 0;
152 for (j = 0; j < 2; j++) {
153 for (k = 0; k < 4; k++) {
154 if (!(j | k)) {
155 dc = bitstream_read(bc, 8);
156 } else {
157 dc = bitstream_read_vlc(bc, c->dc_vlc.table, 9, 2);
158 if (dc == -1)
159 return AVERROR_INVALIDDATA;
160 if (dc == 0x100)
161 dc = bitstream_read(bc, 8);
162 }
163 dc = (dc + prev_dc) & 0xFF;
164 prev_dc = dc;
165 c->block[0] = dc;
166
167 nc = bitstream_read_vlc(bc, c->nc_vlc[vlc_set].table, 9, 1);
168 if (nc == -1)
169 return AVERROR_INVALIDDATA;
170
171 bpos = 1;
172 memset(c->block + 1, 0, 15 * sizeof(*c->block));
173 for (l = 0; l < nc; l++) {
174 ac = bitstream_read_vlc(bc, c->ac_vlc[vlc_set].table, 9, 2);
175 if (ac == -1)
176 return AVERROR_INVALIDDATA;
177 if (ac == 0x1000)
178 ac = bitstream_read(bc, 12);
179 bpos += ac & 0xF;
180 if (bpos >= 16)
181 return AVERROR_INVALIDDATA;
182 val = sign_extend(ac >> 4, 8);
183 c->block[ff_zigzag_scan[bpos++]] = val;
184 }
185 tscc2_idct4_put(c->block, q, dst + k * 4, stride);
186 }
187 dst += 4 * stride;
188 }
189 return 0;
190 }
191
192 static int tscc2_decode_slice(TSCC2Context *c, int mb_y,
193 const uint8_t *buf, int buf_size)
194 {
195 int i, mb_x, q, ret;
196 int off;
197
198 bitstream_init8(&c->bc, buf, buf_size);
199
200 for (mb_x = 0; mb_x < c->mb_width; mb_x++) {
201 q = c->slice_quants[mb_x + c->mb_width * mb_y];
202
203 if (q == 0 || q == 3) // skip block
204 continue;
205 for (i = 0; i < 3; i++) {
206 off = mb_x * 16 + mb_y * 8 * c->pic->linesize[i];
207 ret = tscc2_decode_mb(c, c->q[q - 1], c->quant[q - 1] - 2,
208 c->pic->data[i] + off, c->pic->linesize[i], i);
209 if (ret)
210 return ret;
211 }
212 }
213
214 return 0;
215 }
216
217 static int tscc2_decode_frame(AVCodecContext *avctx, void *data,
218 int *got_frame, AVPacket *avpkt)
219 {
220 const uint8_t *buf = avpkt->data;
221 int buf_size = avpkt->size;
222 TSCC2Context *c = avctx->priv_data;
223 GetByteContext gb;
224 uint32_t frame_type, size;
225 int i, val, len, pos = 0;
226 int num_mb = c->mb_width * c->mb_height;
227 int ret;
228
229 bytestream2_init(&gb, buf, buf_size);
230 frame_type = bytestream2_get_byte(&gb);
231 if (frame_type > 1) {
232 av_log(avctx, AV_LOG_ERROR, "Incorrect frame type %"PRIu32"\n",
233 frame_type);
234 return AVERROR_INVALIDDATA;
235 }
236
237 if ((ret = ff_reget_buffer(avctx, c->pic)) < 0) {
238 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
239 return ret;
240 }
241
242 if (frame_type == 0) {
243 *got_frame = 1;
244 if ((ret = av_frame_ref(data, c->pic)) < 0)
245 return ret;
246
247 return buf_size;
248 }
249
250 if (bytestream2_get_bytes_left(&gb) < 4) {
251 av_log(avctx, AV_LOG_ERROR, "Frame is too short\n");
252 return AVERROR_INVALIDDATA;
253 }
254
255 c->quant[0] = bytestream2_get_byte(&gb);
256 c->quant[1] = bytestream2_get_byte(&gb);
257 if (c->quant[0] < 2 || c->quant[0] > NUM_VLC_SETS + 1 ||
258 c->quant[1] < 2 || c->quant[1] > NUM_VLC_SETS + 1) {
259 av_log(avctx, AV_LOG_ERROR, "Invalid quantisers %d / %d\n",
260 c->quant[0], c->quant[1]);
261 return AVERROR_INVALIDDATA;
262 }
263
264 for (i = 0; i < 3; i++) {
265 c->q[0][i] = tscc2_quants[c->quant[0] - 2][i];
266 c->q[1][i] = tscc2_quants[c->quant[1] - 2][i];
267 }
268
269 bytestream2_skip(&gb, 1);
270
271 size = bytestream2_get_le32(&gb);
272 if (size > bytestream2_get_bytes_left(&gb)) {
273 av_log(avctx, AV_LOG_ERROR, "Slice properties chunk is too large\n");
274 return AVERROR_INVALIDDATA;
275 }
276
277 for (i = 0; i < size; i++) {
278 val = bytestream2_get_byte(&gb);
279 len = val & 0x3F;
280 val >>= 6;
281 if (pos + len > num_mb) {
282 av_log(avctx, AV_LOG_ERROR, "Too many slice properties\n");
283 return AVERROR_INVALIDDATA;
284 }
285 memset(c->slice_quants + pos, val, len);
286 pos += len;
287 }
288 if (pos < num_mb) {
289 av_log(avctx, AV_LOG_ERROR, "Too few slice properties (%d / %d)\n",
290 pos, num_mb);
291 return AVERROR_INVALIDDATA;
292 }
293
294 for (i = 0; i < c->mb_height; i++) {
295 size = bytestream2_peek_byte(&gb);
296 if (size & 1) {
297 size = bytestream2_get_byte(&gb) - 1;
298 } else {
299 size = bytestream2_get_le32(&gb) >> 1;
300 }
301 if (!size) {
302 int skip_row = 1, j, off = i * c->mb_width;
303 for (j = 0; j < c->mb_width; j++) {
304 if (c->slice_quants[off + j] == 1 ||
305 c->slice_quants[off + j] == 2) {
306 skip_row = 0;
307 break;
308 }
309 }
310 if (!skip_row) {
311 av_log(avctx, AV_LOG_ERROR, "Non-skip row with zero size\n");
312 return AVERROR_INVALIDDATA;
313 }
314 }
315 if (bytestream2_get_bytes_left(&gb) < size) {
316 av_log(avctx, AV_LOG_ERROR, "Invalid slice size (%"PRIu32"/%u)\n",
317 size, bytestream2_get_bytes_left(&gb));
318 return AVERROR_INVALIDDATA;
319 }
320 ret = tscc2_decode_slice(c, i, buf + bytestream2_tell(&gb), size);
321 if (ret) {
322 av_log(avctx, AV_LOG_ERROR, "Error decoding slice %d\n", i);
323 return ret;
324 }
325 bytestream2_skip(&gb, size);
326 }
327
328 *got_frame = 1;
329 if ((ret = av_frame_ref(data, c->pic)) < 0)
330 return ret;
331
332 /* always report that the buffer was completely consumed */
333 return buf_size;
334 }
335
336 static av_cold int tscc2_decode_end(AVCodecContext *avctx)
337 {
338 TSCC2Context * const c = avctx->priv_data;
339
340 av_frame_free(&c->pic);
341 av_freep(&c->slice_quants);
342 free_vlcs(c);
343
344 return 0;
345 }
346
347 static av_cold int tscc2_decode_init(AVCodecContext *avctx)
348 {
349 TSCC2Context * const c = avctx->priv_data;
350 int ret;
351
352 c->avctx = avctx;
353
354 avctx->pix_fmt = AV_PIX_FMT_YUV444P;
355
356 if ((ret = init_vlcs(c)) < 0) {
357 av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n");
358 return ret;
359 }
360
361 c->mb_width = FFALIGN(avctx->width, 16) >> 4;
362 c->mb_height = FFALIGN(avctx->height, 8) >> 3;
363 c->slice_quants = av_malloc(c->mb_width * c->mb_height);
364 if (!c->slice_quants) {
365 av_log(avctx, AV_LOG_ERROR, "Cannot allocate slice information\n");
366 free_vlcs(c);
367 return AVERROR(ENOMEM);
368 }
369
370 c->pic = av_frame_alloc();
371 if (!c->pic) {
372 tscc2_decode_end(avctx);
373 return AVERROR(ENOMEM);
374 }
375
376 return 0;
377 }
378
379 AVCodec ff_tscc2_decoder = {
380 .name = "tscc2",
381 .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Codec 2"),
382 .type = AVMEDIA_TYPE_VIDEO,
383 .id = AV_CODEC_ID_TSCC2,
384 .priv_data_size = sizeof(TSCC2Context),
385 .init = tscc2_decode_init,
386 .close = tscc2_decode_end,
387 .decode = tscc2_decode_frame,
388 .capabilities = AV_CODEC_CAP_DR1,
389 };