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
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
|
/*
* Mandsoft Screen Capture Codec decoder
*
* Copyright (c) 2017 Paul B Mahol
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include <zlib.h>
typedef struct MSCCContext {
unsigned bpp;
unsigned int decomp_size;
uint8_t *decomp_buf;
unsigned int uncomp_size;
uint8_t *uncomp_buf;
z_stream zstream;
} MSCCContext;
static int rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb, int bpp)
{
while (bytestream2_get_bytes_left(gb) > 0) {
uint32_t fill;
int j;
unsigned run = bytestream2_get_byte(gb);
if (run) {
switch (avctx->bits_per_coded_sample) {
case 8:
fill = bytestream2_get_byte(gb);
break;
case 16:
fill = bytestream2_get_le16(gb);
break;
case 24:
fill = bytestream2_get_le24(gb);
break;
case 32:
fill = bytestream2_get_le32(gb);
break;
}
for (j = 0; j < run; j++) {
switch (avctx->bits_per_coded_sample) {
case 8:
bytestream2_put_byte(pb, fill);
break;
case 16:
bytestream2_put_le16(pb, fill);
break;
case 24:
bytestream2_put_le24(pb, fill);
break;
case 32:
bytestream2_put_le32(pb, fill);
break;
}
}
} else {
unsigned copy = bytestream2_get_byte(gb);
if (copy == 1) {
return 0;
} else if (copy == 2) {
unsigned x, y;
x = bytestream2_get_byte(gb);
y = bytestream2_get_byte(gb);
bytestream2_skip_p(pb, x * bpp);
bytestream2_skip_p(pb, y * bpp * avctx->width);
} else {
for (j = 0; j < copy; j++) {
switch (avctx->bits_per_coded_sample) {
case 8:
bytestream2_put_byte(pb, bytestream2_get_byte(gb));
break;
case 16:
bytestream2_put_le16(pb, bytestream2_get_le16(gb));
break;
case 24:
bytestream2_put_le24(pb, bytestream2_get_le24(gb));
break;
case 32:
bytestream2_put_le32(pb, bytestream2_get_le32(gb));
break;
}
}
}
}
}
return AVERROR_INVALIDDATA;
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
MSCCContext *s = avctx->priv_data;
AVFrame *frame = data;
GetByteContext gb;
PutByteContext pb;
int ret, j;
if (avpkt->size < 3)
return AVERROR_INVALIDDATA;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
avpkt->data[2] ^= avpkt->data[0];
ret = inflateReset(&s->zstream);
if (ret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
return AVERROR_UNKNOWN;
}
s->zstream.next_in = avpkt->data + 2;
s->zstream.avail_in = avpkt->size - 2;
s->zstream.next_out = s->decomp_buf;
s->zstream.avail_out = s->decomp_size;
ret = inflate(&s->zstream, Z_FINISH);
if (ret != Z_STREAM_END) {
av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
return AVERROR_UNKNOWN;
}
bytestream2_init(&gb, s->decomp_buf, s->zstream.total_out);
bytestream2_init_writer(&pb, s->uncomp_buf, s->uncomp_size);
ret = rle_uncompress(avctx, &gb, &pb, s->bpp);
if (ret)
return ret;
for (j = 0; j < avctx->height; j++) {
memcpy(frame->data[0] + (avctx->height - j - 1) * frame->linesize[0],
s->uncomp_buf + s->bpp * j * avctx->width, s->bpp * avctx->width);
}
frame->key_frame = 1;
frame->pict_type = AV_PICTURE_TYPE_I;
*got_frame = 1;
return avpkt->size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
MSCCContext *s = avctx->priv_data;
int zret;
switch (avctx->bits_per_coded_sample) {
case 8: avctx->pix_fmt = AV_PIX_FMT_GRAY8; 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_BGRA; break;
default:
av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
return AVERROR_INVALIDDATA;
}
s->bpp = avctx->bits_per_coded_sample >> 3;
memset(&s->zstream, 0, sizeof(z_stream));
s->decomp_size = 4 * avctx->height * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
if (!(s->decomp_buf = av_malloc(s->decomp_size)))
return AVERROR(ENOMEM);
s->uncomp_size = 4 * avctx->height * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
if (!(s->uncomp_buf = av_malloc(s->uncomp_size)))
return AVERROR(ENOMEM);
s->zstream.zalloc = Z_NULL;
s->zstream.zfree = Z_NULL;
s->zstream.opaque = Z_NULL;
zret = inflateInit(&s->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_close(AVCodecContext *avctx)
{
MSCCContext *s = avctx->priv_data;
av_freep(&s->decomp_buf);
s->decomp_size = 0;
av_freep(&s->uncomp_buf);
s->uncomp_size = 0;
inflateEnd(&s->zstream);
return 0;
}
AVCodec ff_mscc_decoder = {
.name = "mscc",
.long_name = NULL_IF_CONFIG_SMALL("Mandsoft Screen Capture Codec"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_MSCC,
.priv_data_size = sizeof(MSCCContext),
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};
|