db2805ebafa0a3d375e43ea7ac120523902bf3dc
[libav.git] / libavcodec / tscc.c
1 /*
2 * TechSmith Camtasia decoder
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 * TechSmith Camtasia decoder
25 *
26 * Fourcc: TSCC
27 *
28 * Codec is very simple:
29 * it codes picture (picture difference, really)
30 * with algorithm almost identical to Windows RLE8,
31 * only without padding and with greater pixel sizes,
32 * then this coded picture is packed with ZLib
33 *
34 * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
35 *
36 */
37
38 #include <stdio.h>
39 #include <stdlib.h>
40
41 #include "avcodec.h"
42 #include "internal.h"
43 #include "msrledec.h"
44
45 #include <zlib.h>
46
47
48 /*
49 * Decoder context
50 */
51 typedef struct TsccContext {
52
53 AVCodecContext *avctx;
54 AVFrame pic;
55
56 // Bits per pixel
57 int bpp;
58 // Decompressed data size
59 unsigned int decomp_size;
60 // Decompression buffer
61 unsigned char* decomp_buf;
62 GetByteContext gb;
63 int height;
64 z_stream zstream;
65
66 uint32_t pal[256];
67 } CamtasiaContext;
68
69 /*
70 *
71 * Decode a frame
72 *
73 */
74 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
75 {
76 const uint8_t *buf = avpkt->data;
77 int buf_size = avpkt->size;
78 CamtasiaContext * const c = avctx->priv_data;
79 const unsigned char *encoded = buf;
80 int zret; // Zlib return code
81 int len = buf_size;
82
83 if(c->pic.data[0])
84 avctx->release_buffer(avctx, &c->pic);
85
86 c->pic.reference = 1;
87 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
88 if(ff_get_buffer(avctx, &c->pic) < 0){
89 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
90 return -1;
91 }
92
93 zret = inflateReset(&c->zstream);
94 if (zret != Z_OK) {
95 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
96 return -1;
97 }
98 c->zstream.next_in = encoded;
99 c->zstream.avail_in = len;
100 c->zstream.next_out = c->decomp_buf;
101 c->zstream.avail_out = c->decomp_size;
102 zret = inflate(&c->zstream, Z_FINISH);
103 // Z_DATA_ERROR means empty picture
104 if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
105 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
106 return -1;
107 }
108
109
110 if (zret != Z_DATA_ERROR) {
111 bytestream2_init(&c->gb, c->decomp_buf,
112 c->decomp_size - c->zstream.avail_out);
113 ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, &c->gb);
114 }
115
116 /* make the palette available on the way out */
117 if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
118 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
119
120 if (pal) {
121 c->pic.palette_has_changed = 1;
122 memcpy(c->pal, pal, AVPALETTE_SIZE);
123 }
124 memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE);
125 }
126
127 *data_size = sizeof(AVFrame);
128 *(AVFrame*)data = c->pic;
129
130 /* always report that the buffer was completely consumed */
131 return buf_size;
132 }
133
134
135
136 /*
137 *
138 * Init tscc decoder
139 *
140 */
141 static av_cold int decode_init(AVCodecContext *avctx)
142 {
143 CamtasiaContext * const c = avctx->priv_data;
144 int zret; // Zlib return code
145
146 c->avctx = avctx;
147
148 c->height = avctx->height;
149
150 // Needed if zlib unused or init aborted before inflateInit
151 memset(&c->zstream, 0, sizeof(z_stream));
152 switch(avctx->bits_per_coded_sample){
153 case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
154 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
155 case 24:
156 avctx->pix_fmt = AV_PIX_FMT_BGR24;
157 break;
158 case 32: avctx->pix_fmt = AV_PIX_FMT_RGB32; break;
159 default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
160 return -1;
161 }
162 c->bpp = avctx->bits_per_coded_sample;
163 // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
164 c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
165
166 /* Allocate decompression buffer */
167 if (c->decomp_size) {
168 if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
169 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
170 return 1;
171 }
172 }
173
174 c->zstream.zalloc = Z_NULL;
175 c->zstream.zfree = Z_NULL;
176 c->zstream.opaque = Z_NULL;
177 zret = inflateInit(&c->zstream);
178 if (zret != Z_OK) {
179 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
180 return 1;
181 }
182
183 return 0;
184 }
185
186
187
188 /*
189 *
190 * Uninit tscc decoder
191 *
192 */
193 static av_cold int decode_end(AVCodecContext *avctx)
194 {
195 CamtasiaContext * const c = avctx->priv_data;
196
197 av_freep(&c->decomp_buf);
198
199 if (c->pic.data[0])
200 avctx->release_buffer(avctx, &c->pic);
201 inflateEnd(&c->zstream);
202
203 return 0;
204 }
205
206 AVCodec ff_tscc_decoder = {
207 .name = "camtasia",
208 .type = AVMEDIA_TYPE_VIDEO,
209 .id = AV_CODEC_ID_TSCC,
210 .priv_data_size = sizeof(CamtasiaContext),
211 .init = decode_init,
212 .close = decode_end,
213 .decode = decode_frame,
214 .capabilities = CODEC_CAP_DR1,
215 .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
216 };