lavc: fix decode_frame() third parameter semantics for video decoders
[libav.git] / libavcodec / qpeg.c
1 /*
2 * QPEG codec
3 * Copyright (c) 2004 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 * QPEG codec.
25 */
26
27 #include "avcodec.h"
28 #include "bytestream.h"
29
30 typedef struct QpegContext{
31 AVCodecContext *avctx;
32 AVFrame pic;
33 uint8_t *refdata;
34 uint32_t pal[256];
35 GetByteContext buffer;
36 } QpegContext;
37
38 static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst,
39 int stride, int width, int height)
40 {
41 int i;
42 int code;
43 int c0, c1;
44 int run, copy;
45 int filled = 0;
46 int rows_to_go;
47
48 rows_to_go = height;
49 height--;
50 dst = dst + height * stride;
51
52 while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (rows_to_go > 0)) {
53 code = bytestream2_get_byte(&qctx->buffer);
54 run = copy = 0;
55 if(code == 0xFC) /* end-of-picture code */
56 break;
57 if(code >= 0xF8) { /* very long run */
58 c0 = bytestream2_get_byte(&qctx->buffer);
59 c1 = bytestream2_get_byte(&qctx->buffer);
60 run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2;
61 } else if (code >= 0xF0) { /* long run */
62 c0 = bytestream2_get_byte(&qctx->buffer);
63 run = ((code & 0xF) << 8) + c0 + 2;
64 } else if (code >= 0xE0) { /* short run */
65 run = (code & 0x1F) + 2;
66 } else if (code >= 0xC0) { /* very long copy */
67 c0 = bytestream2_get_byte(&qctx->buffer);
68 c1 = bytestream2_get_byte(&qctx->buffer);
69 copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1;
70 } else if (code >= 0x80) { /* long copy */
71 c0 = bytestream2_get_byte(&qctx->buffer);
72 copy = ((code & 0x7F) << 8) + c0 + 1;
73 } else { /* short copy */
74 copy = code + 1;
75 }
76
77 /* perform actual run or copy */
78 if(run) {
79 int p;
80
81 p = bytestream2_get_byte(&qctx->buffer);
82 for(i = 0; i < run; i++) {
83 dst[filled++] = p;
84 if (filled >= width) {
85 filled = 0;
86 dst -= stride;
87 rows_to_go--;
88 if(rows_to_go <= 0)
89 break;
90 }
91 }
92 } else {
93 for(i = 0; i < copy; i++) {
94 dst[filled++] = bytestream2_get_byte(&qctx->buffer);
95 if (filled >= width) {
96 filled = 0;
97 dst -= stride;
98 rows_to_go--;
99 if(rows_to_go <= 0)
100 break;
101 }
102 }
103 }
104 }
105 }
106
107 static const int qpeg_table_h[16] =
108 { 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04};
109 static const int qpeg_table_w[16] =
110 { 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04};
111
112 /* Decodes delta frames */
113 static void qpeg_decode_inter(QpegContext *qctx, uint8_t *dst,
114 int stride, int width, int height,
115 int delta, const uint8_t *ctable,
116 uint8_t *refdata)
117 {
118 int i, j;
119 int code;
120 int filled = 0;
121 int orig_height;
122
123 /* copy prev frame */
124 for(i = 0; i < height; i++)
125 memcpy(refdata + (i * width), dst + (i * stride), width);
126
127 orig_height = height;
128 height--;
129 dst = dst + height * stride;
130
131 while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (height >= 0)) {
132 code = bytestream2_get_byte(&qctx->buffer);
133
134 if(delta) {
135 /* motion compensation */
136 while((code & 0xF0) == 0xF0) {
137 if(delta == 1) {
138 int me_idx;
139 int me_w, me_h, me_x, me_y;
140 uint8_t *me_plane;
141 int corr, val;
142
143 /* get block size by index */
144 me_idx = code & 0xF;
145 me_w = qpeg_table_w[me_idx];
146 me_h = qpeg_table_h[me_idx];
147
148 /* extract motion vector */
149 corr = bytestream2_get_byte(&qctx->buffer);
150
151 val = corr >> 4;
152 if(val > 7)
153 val -= 16;
154 me_x = val;
155
156 val = corr & 0xF;
157 if(val > 7)
158 val -= 16;
159 me_y = val;
160
161 /* check motion vector */
162 if ((me_x + filled < 0) || (me_x + me_w + filled > width) ||
163 (height - me_y - me_h < 0) || (height - me_y > orig_height) ||
164 (filled + me_w > width) || (height - me_h < 0))
165 av_log(NULL, AV_LOG_ERROR, "Bogus motion vector (%i,%i), block size %ix%i at %i,%i\n",
166 me_x, me_y, me_w, me_h, filled, height);
167 else {
168 /* do motion compensation */
169 me_plane = refdata + (filled + me_x) + (height - me_y) * width;
170 for(j = 0; j < me_h; j++) {
171 for(i = 0; i < me_w; i++)
172 dst[filled + i - (j * stride)] = me_plane[i - (j * width)];
173 }
174 }
175 }
176 code = bytestream2_get_byte(&qctx->buffer);
177 }
178 }
179
180 if(code == 0xE0) /* end-of-picture code */
181 break;
182 if(code > 0xE0) { /* run code: 0xE1..0xFF */
183 int p;
184
185 code &= 0x1F;
186 p = bytestream2_get_byte(&qctx->buffer);
187 for(i = 0; i <= code; i++) {
188 dst[filled++] = p;
189 if(filled >= width) {
190 filled = 0;
191 dst -= stride;
192 height--;
193 }
194 }
195 } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */
196 code &= 0x1F;
197
198 for(i = 0; i <= code; i++) {
199 dst[filled++] = bytestream2_get_byte(&qctx->buffer);
200 if(filled >= width) {
201 filled = 0;
202 dst -= stride;
203 height--;
204 }
205 }
206 } else if(code >= 0x80) { /* skip code: 0x80..0xBF */
207 int skip;
208
209 code &= 0x3F;
210 /* codes 0x80 and 0x81 are actually escape codes,
211 skip value minus constant is in the next byte */
212 if(!code)
213 skip = bytestream2_get_byte(&qctx->buffer) + 64;
214 else if(code == 1)
215 skip = bytestream2_get_byte(&qctx->buffer) + 320;
216 else
217 skip = code;
218 filled += skip;
219 while( filled >= width) {
220 filled -= width;
221 dst -= stride;
222 height--;
223 if(height < 0)
224 break;
225 }
226 } else {
227 /* zero code treated as one-pixel skip */
228 if(code) {
229 dst[filled++] = ctable[code & 0x7F];
230 }
231 else
232 filled++;
233 if(filled >= width) {
234 filled = 0;
235 dst -= stride;
236 height--;
237 }
238 }
239 }
240 }
241
242 static int decode_frame(AVCodecContext *avctx,
243 void *data, int *got_frame,
244 AVPacket *avpkt)
245 {
246 uint8_t ctable[128];
247 QpegContext * const a = avctx->priv_data;
248 AVFrame * const p = &a->pic;
249 uint8_t* outdata;
250 int delta;
251 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
252
253 if (avpkt->size < 0x86) {
254 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
255 return AVERROR_INVALIDDATA;
256 }
257
258 bytestream2_init(&a->buffer, avpkt->data, avpkt->size);
259 p->reference = 3;
260 if (avctx->reget_buffer(avctx, p) < 0) {
261 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
262 return -1;
263 }
264 outdata = a->pic.data[0];
265 bytestream2_skip(&a->buffer, 4);
266 bytestream2_get_buffer(&a->buffer, ctable, 128);
267 bytestream2_skip(&a->buffer, 1);
268
269 delta = bytestream2_get_byte(&a->buffer);
270 if(delta == 0x10) {
271 qpeg_decode_intra(a, outdata, a->pic.linesize[0], avctx->width, avctx->height);
272 } else {
273 qpeg_decode_inter(a, outdata, a->pic.linesize[0], avctx->width, avctx->height, delta, ctable, a->refdata);
274 }
275
276 /* make the palette available on the way out */
277 if (pal) {
278 a->pic.palette_has_changed = 1;
279 memcpy(a->pal, pal, AVPALETTE_SIZE);
280 }
281 memcpy(a->pic.data[1], a->pal, AVPALETTE_SIZE);
282
283 *got_frame = 1;
284 *(AVFrame*)data = a->pic;
285
286 return avpkt->size;
287 }
288
289 static av_cold int decode_init(AVCodecContext *avctx){
290 QpegContext * const a = avctx->priv_data;
291
292 a->avctx = avctx;
293 avctx->pix_fmt= AV_PIX_FMT_PAL8;
294 a->refdata = av_malloc(avctx->width * avctx->height);
295
296 return 0;
297 }
298
299 static av_cold int decode_end(AVCodecContext *avctx){
300 QpegContext * const a = avctx->priv_data;
301 AVFrame * const p = &a->pic;
302
303 if(p->data[0])
304 avctx->release_buffer(avctx, p);
305
306 av_free(a->refdata);
307 return 0;
308 }
309
310 AVCodec ff_qpeg_decoder = {
311 .name = "qpeg",
312 .type = AVMEDIA_TYPE_VIDEO,
313 .id = AV_CODEC_ID_QPEG,
314 .priv_data_size = sizeof(QpegContext),
315 .init = decode_init,
316 .close = decode_end,
317 .decode = decode_frame,
318 .capabilities = CODEC_CAP_DR1,
319 .long_name = NULL_IF_CONFIG_SMALL("Q-team QPEG"),
320 };