1 /*
2 * Mandsoft Screen Capture Codec decoder
3 *
4 * Copyright (c) 2017 Paul B Mahol
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "codec_internal.h"
30 #include "internal.h"
31 #include "zlib_wrapper.h"
32
33 #include <zlib.h>
34
35 typedef struct MSCCContext {
36 unsigned bpp;
37 unsigned int decomp_size;
38 uint8_t *decomp_buf;
39 unsigned int uncomp_size;
40 uint8_t *uncomp_buf;
41 FFZStream zstream;
42
43 uint32_t pal[256];
44 } MSCCContext;
45
rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb)46 static int rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb)
47 {
48 MSCCContext *s = avctx->priv_data;
49 unsigned x = 0, y = 0;
50
51 while (bytestream2_get_bytes_left(gb) > 0) {
52 uint32_t fill;
53 int j;
54 unsigned run = bytestream2_get_byte(gb);
55
56 if (run) {
57 switch (avctx->bits_per_coded_sample) {
58 case 8:
59 fill = bytestream2_get_byte(gb);
60 break;
61 case 16:
62 fill = bytestream2_get_le16(gb);
63 break;
64 case 24:
65 fill = bytestream2_get_le24(gb);
66 break;
67 case 32:
68 fill = bytestream2_get_le32(gb);
69 break;
70 }
71
72 for (j = 0; j < run; j++) {
73 switch (avctx->bits_per_coded_sample) {
74 case 8:
75 bytestream2_put_byte(pb, fill);
76 break;
77 case 16:
78 bytestream2_put_le16(pb, fill);
79 break;
80 case 24:
81 bytestream2_put_le24(pb, fill);
82 break;
83 case 32:
84 bytestream2_put_le32(pb, fill);
85 break;
86 }
87 }
88 x += run;
89 } else {
90 unsigned copy = bytestream2_get_byte(gb);
91
92 if (copy == 0) {
93 x = 0;
94 y++;
95 bytestream2_seek_p(pb, y * avctx->width * s->bpp, SEEK_SET);
96 } else if (copy == 1) {
97 return 0;
98 } else if (copy == 2) {
99
100 x += bytestream2_get_byte(gb);
101 y += bytestream2_get_byte(gb);
102
103 bytestream2_seek_p(pb, y * avctx->width * s->bpp + x * s->bpp, SEEK_SET);
104 } else {
105 for (j = 0; j < copy; j++) {
106 switch (avctx->bits_per_coded_sample) {
107 case 8:
108 bytestream2_put_byte(pb, bytestream2_get_byte(gb));
109 break;
110 case 16:
111 bytestream2_put_le16(pb, bytestream2_get_le16(gb));
112 break;
113 case 24:
114 bytestream2_put_le24(pb, bytestream2_get_le24(gb));
115 break;
116 case 32:
117 bytestream2_put_le32(pb, bytestream2_get_le32(gb));
118 break;
119 }
120 }
121
122 if (s->bpp == 1 && (copy & 1))
123 bytestream2_skip(gb, 1);
124 x += copy;
125 }
126 }
127 }
128
129 return AVERROR_INVALIDDATA;
130 }
131
decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)132 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
133 int *got_frame, AVPacket *avpkt)
134 {
135 MSCCContext *s = avctx->priv_data;
136 z_stream *const zstream = &s->zstream.zstream;
137 const uint8_t *buf = avpkt->data;
138 int buf_size = avpkt->size;
139 GetByteContext gb;
140 PutByteContext pb;
141 int ret, j;
142
143 if (avpkt->size < 3)
144 return buf_size;
145
146 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
147 return ret;
148
149 if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
150 size_t size;
151 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
152
153 if (pal && size == AVPALETTE_SIZE) {
154 frame->palette_has_changed = 1;
155 for (j = 0; j < 256; j++)
156 s->pal[j] = 0xFF000000 | AV_RL32(pal + j * 4);
157 } else if (pal) {
158 av_log(avctx, AV_LOG_ERROR,
159 "Palette size %"SIZE_SPECIFIER" is wrong\n", size);
160 }
161 memcpy(frame->data[1], s->pal, AVPALETTE_SIZE);
162 }
163
164 ret = inflateReset(zstream);
165 if (ret != Z_OK) {
166 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
167 return AVERROR_UNKNOWN;
168 }
169 zstream->next_out = s->decomp_buf;
170 zstream->avail_out = s->decomp_size;
171 if (avctx->codec_id == AV_CODEC_ID_MSCC) {
172 const uint8_t start = avpkt->data[2] ^ avpkt->data[0];
173
174 zstream->next_in = &start;
175 zstream->avail_in = 1;
176 ret = inflate(zstream, Z_NO_FLUSH);
177 if (ret != Z_OK || zstream->avail_in != 0)
178 goto inflate_error;
179
180 buf += 3;
181 buf_size -= 3;
182 }
183 zstream->next_in = buf;
184 zstream->avail_in = buf_size;
185 ret = inflate(zstream, Z_FINISH);
186 if (ret != Z_STREAM_END) {
187 inflate_error:
188 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
189 return AVERROR_UNKNOWN;
190 }
191
192 bytestream2_init(&gb, s->decomp_buf, zstream->total_out);
193 bytestream2_init_writer(&pb, s->uncomp_buf, s->uncomp_size);
194
195 ret = rle_uncompress(avctx, &gb, &pb);
196 if (ret)
197 return ret;
198
199 for (j = 0; j < avctx->height; j++) {
200 memcpy(frame->data[0] + (avctx->height - j - 1) * frame->linesize[0],
201 s->uncomp_buf + s->bpp * j * avctx->width, s->bpp * avctx->width);
202 }
203
204 frame->key_frame = 1;
205 frame->pict_type = AV_PICTURE_TYPE_I;
206
207 *got_frame = 1;
208
209 return avpkt->size;
210 }
211
decode_init(AVCodecContext *avctx)212 static av_cold int decode_init(AVCodecContext *avctx)
213 {
214 MSCCContext *s = avctx->priv_data;
215 int stride;
216
217 switch (avctx->bits_per_coded_sample) {
218 case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
219 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
220 case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
221 case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
222 default:
223 av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
224 return AVERROR_INVALIDDATA;
225 }
226
227 s->bpp = avctx->bits_per_coded_sample >> 3;
228 stride = 4 * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
229
230 s->decomp_size = 2 * avctx->height * stride;
231 if (!(s->decomp_buf = av_malloc(s->decomp_size)))
232 return AVERROR(ENOMEM);
233
234 s->uncomp_size = avctx->height * stride;
235 if (!(s->uncomp_buf = av_malloc(s->uncomp_size)))
236 return AVERROR(ENOMEM);
237
238 return ff_inflate_init(&s->zstream, avctx);
239 }
240
decode_close(AVCodecContext *avctx)241 static av_cold int decode_close(AVCodecContext *avctx)
242 {
243 MSCCContext *s = avctx->priv_data;
244
245 av_freep(&s->decomp_buf);
246 s->decomp_size = 0;
247 av_freep(&s->uncomp_buf);
248 s->uncomp_size = 0;
249 ff_inflate_end(&s->zstream);
250
251 return 0;
252 }
253
254 const FFCodec ff_mscc_decoder = {
255 .p.name = "mscc",
256 .p.long_name = NULL_IF_CONFIG_SMALL("Mandsoft Screen Capture Codec"),
257 .p.type = AVMEDIA_TYPE_VIDEO,
258 .p.id = AV_CODEC_ID_MSCC,
259 .priv_data_size = sizeof(MSCCContext),
260 .init = decode_init,
261 .close = decode_close,
262 FF_CODEC_DECODE_CB(decode_frame),
263 .p.capabilities = AV_CODEC_CAP_DR1,
264 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
265 };
266
267 const FFCodec ff_srgc_decoder = {
268 .p.name = "srgc",
269 .p.long_name = NULL_IF_CONFIG_SMALL("Screen Recorder Gold Codec"),
270 .p.type = AVMEDIA_TYPE_VIDEO,
271 .p.id = AV_CODEC_ID_SRGC,
272 .priv_data_size = sizeof(MSCCContext),
273 .init = decode_init,
274 .close = decode_close,
275 FF_CODEC_DECODE_CB(decode_frame),
276 .p.capabilities = AV_CODEC_CAP_DR1,
277 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
278 };
279