Some consts for cscd decoder helper functions
[libav.git] / libavcodec / cscd.c
1 /*
2 * CamStudio decoder
3 * Copyright (c) 2006 Reimar Doeffinger
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21 #include <stdio.h>
22 #include <stdlib.h>
23
24 #include "avcodec.h"
25
26 #ifdef CONFIG_ZLIB
27 #include <zlib.h>
28 #endif
29 #include "lzo.h"
30
31 typedef struct {
32 AVFrame pic;
33 int linelen, height, bpp;
34 unsigned int decomp_size;
35 unsigned char* decomp_buf;
36 } CamStudioContext;
37
38 static void copy_frame_default(AVFrame *f, const uint8_t *src,
39 int linelen, int height) {
40 int i;
41 uint8_t *dst = f->data[0];
42 dst += (height - 1) * f->linesize[0];
43 for (i = height; i; i--) {
44 memcpy(dst, src, linelen);
45 src += linelen;
46 dst -= f->linesize[0];
47 }
48 }
49
50 static void add_frame_default(AVFrame *f, const uint8_t *src,
51 int linelen, int height) {
52 int i, j;
53 uint8_t *dst = f->data[0];
54 dst += (height - 1) * f->linesize[0];
55 for (i = height; i; i--) {
56 for (j = linelen; j; j--)
57 *dst++ += *src++;
58 dst -= f->linesize[0] + linelen;
59 }
60 }
61
62 #ifndef WORDS_BIGENDIAN
63 #define copy_frame_16 copy_frame_default
64 #define copy_frame_32 copy_frame_default
65 #define add_frame_16 add_frame_default
66 #define add_frame_32 add_frame_default
67 #else
68 static void copy_frame_16(AVFrame *f, const uint8_t *src,
69 int linelen, int height) {
70 int i, j;
71 uint8_t *dst = f->data[0];
72 dst += (height - 1) * f->linesize[0];
73 for (i = height; i; i--) {
74 for (j = linelen / 2; j; j--) {
75 dst[0] = src[1];
76 dst[1] = src[0];
77 src += 2;
78 dst += 2;
79 }
80 dst -= f->linesize[0] + linelen;
81 }
82 }
83
84 static void copy_frame_32(AVFrame *f, const uint8_t *src,
85 int linelen, int height) {
86 int i, j;
87 uint8_t *dst = f->data[0];
88 dst += (height - 1) * f->linesize[0];
89 for (i = height; i; i--) {
90 for (j = linelen / 4; j; j--) {
91 dst[0] = src[3];
92 dst[1] = src[2];
93 dst[2] = src[1];
94 dst[3] = src[0];
95 src += 4;
96 dst += 4;
97 }
98 dst -= f->linesize[0] + linelen;
99 }
100 }
101
102 static void add_frame_16(AVFrame *f, const uint8_t *src,
103 int linelen, int height) {
104 int i, j;
105 uint8_t *dst = f->data[0];
106 dst += (height - 1) * f->linesize[0];
107 for (i = height; i; i--) {
108 for (j = linelen / 2; j; j--) {
109 dst[0] += src[1];
110 dst[1] += src[0];
111 src += 2;
112 dst += 2;
113 }
114 dst -= f->linesize[0] + linelen;
115 }
116 }
117
118 static void add_frame_32(AVFrame *f, const uint8_t *src,
119 int linelen, int height) {
120 int i, j;
121 uint8_t *dst = f->data[0];
122 dst += (height - 1) * f->linesize[0];
123 for (i = height; i; i--) {
124 for (j = linelen / 4; j; j--) {
125 dst[0] += src[3];
126 dst[1] += src[2];
127 dst[2] += src[1];
128 dst[3] += src[0];
129 src += 4;
130 dst += 4;
131 }
132 dst -= f->linesize[0] + linelen;
133 }
134 }
135 #endif
136
137 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
138 const uint8_t *buf, int buf_size) {
139 CamStudioContext *c = avctx->priv_data;
140 AVFrame *picture = data;
141
142 if (buf_size < 2) {
143 av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
144 return -1;
145 }
146
147 if (c->pic.data[0])
148 avctx->release_buffer(avctx, &c->pic);
149 c->pic.reference = 1;
150 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE |
151 FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
152 if (avctx->get_buffer(avctx, &c->pic) < 0) {
153 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
154 return -1;
155 }
156
157 // decompress data
158 switch ((buf[0] >> 1) & 7) {
159 case 0: { // lzo compression
160 int outlen = c->decomp_size, inlen = buf_size - 2;
161 if (lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen))
162 av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
163 break;
164 }
165 case 1: { // zlib compression
166 #ifdef CONFIG_ZLIB
167 unsigned long dlen = c->decomp_size;
168 if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK)
169 av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n");
170 break;
171 #else
172 av_log(avctx, AV_LOG_ERROR, "compiled without zlib support\n");
173 return -1;
174 #endif
175 }
176 default:
177 av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
178 return -1;
179 }
180
181 // flip upside down, add difference frame
182 if (buf[0] & 1) { // keyframe
183 c->pic.pict_type = FF_I_TYPE;
184 c->pic.key_frame = 1;
185 switch (c->bpp) {
186 case 16:
187 copy_frame_16(&c->pic, c->decomp_buf, c->linelen, c->height);
188 break;
189 case 32:
190 copy_frame_32(&c->pic, c->decomp_buf, c->linelen, c->height);
191 break;
192 default:
193 copy_frame_default(&c->pic, c->decomp_buf, c->linelen, c->height);
194 }
195 } else {
196 c->pic.pict_type = FF_P_TYPE;
197 c->pic.key_frame = 0;
198 switch (c->bpp) {
199 case 16:
200 add_frame_16(&c->pic, c->decomp_buf, c->linelen, c->height);
201 break;
202 case 32:
203 add_frame_32(&c->pic, c->decomp_buf, c->linelen, c->height);
204 break;
205 default:
206 add_frame_default(&c->pic, c->decomp_buf, c->linelen, c->height);
207 }
208 }
209
210 *picture = c->pic;
211 *data_size = sizeof(AVFrame);
212 return buf_size;
213 }
214
215 static int decode_init(AVCodecContext *avctx) {
216 CamStudioContext *c = avctx->priv_data;
217 if (avcodec_check_dimensions(avctx, avctx->height, avctx->width) < 0) {
218 return 1;
219 }
220 switch (avctx->bits_per_sample) {
221 case 16: avctx->pix_fmt = PIX_FMT_RGB555; break;
222 case 24: avctx->pix_fmt = PIX_FMT_BGR24; break;
223 case 32: avctx->pix_fmt = PIX_FMT_RGB32; break;
224 default:
225 av_log(avctx, AV_LOG_ERROR,
226 "CamStudio codec error: invalid depth %i bpp\n",
227 avctx->bits_per_sample);
228 return 1;
229 }
230 c->bpp = avctx->bits_per_sample;
231 c->pic.data[0] = NULL;
232 c->linelen = avctx->width * avctx->bits_per_sample / 8;
233 c->height = avctx->height;
234 c->decomp_size = c->height * c->linelen;
235 c->decomp_buf = av_malloc(c->decomp_size + LZO_OUTPUT_PADDING);
236 if (!c->decomp_buf) {
237 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
238 return 1;
239 }
240 return 0;
241 }
242
243 static int decode_end(AVCodecContext *avctx) {
244 CamStudioContext *c = avctx->priv_data;
245 av_freep(&c->decomp_buf);
246 if (c->pic.data[0])
247 avctx->release_buffer(avctx, &c->pic);
248 return 0;
249 }
250
251 AVCodec cscd_decoder = {
252 "camstudio",
253 CODEC_TYPE_VIDEO,
254 CODEC_ID_CSCD,
255 sizeof(CamStudioContext),
256 decode_init,
257 NULL,
258 decode_end,
259 decode_frame,
260 CODEC_CAP_DR1,
261 };
262