1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/*
* TechSmith Camtasia decoder
* Copyright (c) 2004 Konstantin Shishkov
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* TechSmith Camtasia decoder
*
* Fourcc: TSCC
*
* Codec is very simple:
* it codes picture (picture difference, really)
* with algorithm almost identical to Windows RLE8,
* only without padding and with greater pixel sizes,
* then this coded picture is packed with ZLib
*
* Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
*
*/
#include <stdio.h>
#include <stdlib.h>
#include "avcodec.h"
#include "internal.h"
#include "msrledec.h"
#include <zlib.h>
typedef struct TsccContext {
AVCodecContext *avctx;
// Bits per pixel
int bpp;
// Decompressed data size
unsigned int decomp_size;
// Decompression buffer
unsigned char* decomp_buf;
GetByteContext gb;
int height;
z_stream zstream;
uint32_t pal[256];
} CamtasiaContext;
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
CamtasiaContext * const c = avctx->priv_data;
const unsigned char *encoded = buf;
AVFrame *frame = data;
int zret; // Zlib return code
int ret, len = buf_size;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0){
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
zret = inflateReset(&c->zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
return AVERROR_UNKNOWN;
}
c->zstream.next_in = encoded;
c->zstream.avail_in = len;
c->zstream.next_out = c->decomp_buf;
c->zstream.avail_out = c->decomp_size;
zret = inflate(&c->zstream, Z_FINISH);
// Z_DATA_ERROR means empty picture
if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
return AVERROR_UNKNOWN;
}
if (zret != Z_DATA_ERROR) {
bytestream2_init(&c->gb, c->decomp_buf,
c->decomp_size - c->zstream.avail_out);
ff_msrle_decode(avctx, (AVPicture*)frame, c->bpp, &c->gb);
}
/* make the palette available on the way out */
if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
if (pal) {
frame->palette_has_changed = 1;
memcpy(c->pal, pal, AVPALETTE_SIZE);
}
memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
}
*got_frame = 1;
/* always report that the buffer was completely consumed */
return buf_size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
CamtasiaContext * const c = avctx->priv_data;
int zret; // Zlib return code
c->avctx = avctx;
c->height = avctx->height;
// Needed if zlib unused or init aborted before inflateInit
memset(&c->zstream, 0, sizeof(z_stream));
switch(avctx->bits_per_coded_sample){
case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
case 24:
avctx->pix_fmt = AV_PIX_FMT_BGR24;
break;
case 32: avctx->pix_fmt = AV_PIX_FMT_RGB32; break;
default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
return AVERROR_INVALIDDATA;
}
c->bpp = avctx->bits_per_coded_sample;
// buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
/* Allocate decompression buffer */
if (c->decomp_size) {
if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
return AVERROR(ENOMEM);
}
}
c->zstream.zalloc = Z_NULL;
c->zstream.zfree = Z_NULL;
c->zstream.opaque = Z_NULL;
zret = inflateInit(&c->zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
return AVERROR_UNKNOWN;
}
return 0;
}
static av_cold int decode_end(AVCodecContext *avctx)
{
CamtasiaContext * const c = avctx->priv_data;
av_freep(&c->decomp_buf);
inflateEnd(&c->zstream);
return 0;
}
AVCodec ff_tscc_decoder = {
.name = "camtasia",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_TSCC,
.priv_data_size = sizeof(CamtasiaContext),
.init = decode_init,
.close = decode_end,
.decode = decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
};
|
