5、46号文掀起监管风暴 银行业“三套利”时代

Line	Branch	Exec	Source
1			/*
2			* MatchWare Screen Capture Codec decoder
3			*
4			* Copyright (c) 2018 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
25			#include "libavutil/mem.h"
26			#include "avcodec.h"
27			#include "bytestream.h"
28			#include "codec_internal.h"
29			#include "decode.h"
30			#include "zlib_wrapper.h"
31
32			#include <zlib.h>
33
34			typedef struct MWSCContext {
35			unsigned int decomp_size;
36			uint8_t *decomp_buf;
37			AVFrame *prev_frame;
38			FFZStream zstream;
39			} MWSCContext;
40
41		✗	static int rle_uncompress(GetByteContext *gb, PutByteContext *pb, GetByteContext *gbp,
42			int width, int height, int stride, int pb_linesize, int gbp_linesize)
43			{
44		✗	int intra = 1, w = 0;
45
46		✗	bytestream2_seek_p(pb, (height - 1) * pb_linesize, SEEK_SET);
47
48		✗	while (bytestream2_get_bytes_left(gb) > 0) {
49		✗	uint32_t fill = bytestream2_get_le24(gb);
50		✗	unsigned run = bytestream2_get_byte(gb);
51
52		✗	if (run == 0) {
53		✗	run = bytestream2_get_le32(gb);
54
55		✗	if (bytestream2_tell_p(pb) + width - w < run)
56		✗	return AVERROR_INVALIDDATA;
57
58		✗	for (int j = 0; j < run; j++, w++) {
59		✗	if (w == width) {
60		✗	w = 0;
61		✗	bytestream2_seek_p(pb, -(pb_linesize + stride), SEEK_CUR);
62			}
63		✗	bytestream2_put_le24(pb, fill);
64			}
65		✗	} else if (run == 255) {
66		✗	int pos = bytestream2_tell_p(pb);
67
68		✗	bytestream2_seek(gbp, pos, SEEK_SET);
69
70		✗	if (pos + width - w < fill)
71		✗	return AVERROR_INVALIDDATA;
72
73		✗	for (int j = 0; j < fill; j++, w++) {
74		✗	if (w == width) {
75		✗	w = 0;
76		✗	bytestream2_seek_p(pb, -(pb_linesize + stride), SEEK_CUR);
77		✗	bytestream2_seek(gbp, -(gbp_linesize + stride), SEEK_CUR);
78			}
79		✗	bytestream2_put_le24(pb, bytestream2_get_le24(gbp));
80			}
81
82		✗	intra = 0;
83			} else {
84		✗	if (bytestream2_tell_p(pb) + width - w < run)
85		✗	return AVERROR_INVALIDDATA;
86
87		✗	for (int j = 0; j < run; j++, w++) {
88		✗	if (w == width) {
89		✗	w = 0;
90		✗	bytestream2_seek_p(pb, -(pb_linesize + stride), SEEK_CUR);
91			}
92		✗	bytestream2_put_le24(pb, fill);
93			}
94			}
95			}
96
97		✗	return intra;
98			}
99
100		✗	static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
101			int *got_frame, AVPacket *avpkt)
102			{
103		✗	MWSCContext *s = avctx->priv_data;
104		✗	z_stream *const zstream = &s->zstream.zstream;
105		✗	const uint8_t *buf = avpkt->data;
106		✗	int buf_size = avpkt->size;
107			GetByteContext gb;
108			GetByteContext gbp;
109			PutByteContext pb;
110			int ret;
111
112		✗	ret = inflateReset(zstream);
113		✗	if (ret != Z_OK) {
114		✗	av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
115		✗	return AVERROR_EXTERNAL;
116			}
117		✗	zstream->next_in = buf;
118		✗	zstream->avail_in = buf_size;
119		✗	zstream->next_out = s->decomp_buf;
120		✗	zstream->avail_out = s->decomp_size;
121		✗	ret = inflate(zstream, Z_FINISH);
122		✗	if (ret != Z_STREAM_END) {
123		✗	av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
124		✗	return AVERROR_EXTERNAL;
125			}
126
127		✗	if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
128		✗	return ret;
129
130		✗	bytestream2_init(&gb, s->decomp_buf, zstream->total_out);
131		✗	bytestream2_init(&gbp, s->prev_frame->data[0], avctx->height * s->prev_frame->linesize[0]);
132		✗	bytestream2_init_writer(&pb, frame->data[0], avctx->height * frame->linesize[0]);
133
134		✗	if (rle_uncompress(&gb, &pb, &gbp, avctx->width, avctx->height, avctx->width * 3,
135		✗	frame->linesize[0], s->prev_frame->linesize[0]))
136		✗	frame->flags |= AV_FRAME_FLAG_KEY;
137			else
138		✗	frame->flags &= ~AV_FRAME_FLAG_KEY;
139
140		✗	frame->pict_type = (frame->flags & AV_FRAME_FLAG_KEY) ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
141
142		✗	if ((ret = av_frame_replace(s->prev_frame, frame)) < 0)
143		✗	return ret;
144
145		✗	*got_frame = 1;
146
147		✗	return avpkt->size;
148			}
149
150		✗	static av_cold int decode_init(AVCodecContext *avctx)
151			{
152		✗	MWSCContext *s = avctx->priv_data;
153			int64_t size;
154
155		✗	avctx->pix_fmt = AV_PIX_FMT_BGR24;
156
157		✗	size = 32LL * avctx->height * avctx->width;
158		✗	if (size >= INT32_MAX)
159		✗	return AVERROR_INVALIDDATA;
160		✗	s->decomp_size = size;
161		✗	if (!(s->decomp_buf = av_malloc(s->decomp_size)))
162		✗	return AVERROR(ENOMEM);
163
164		✗	s->prev_frame = av_frame_alloc();
165		✗	if (!s->prev_frame)
166		✗	return AVERROR(ENOMEM);
167
168		✗	return ff_inflate_init(&s->zstream, avctx);
169			}
170
171		✗	static av_cold int decode_close(AVCodecContext *avctx)
172			{
173		✗	MWSCContext *s = avctx->priv_data;
174
175		✗	av_frame_free(&s->prev_frame);
176		✗	av_freep(&s->decomp_buf);
177		✗	s->decomp_size = 0;
178		✗	ff_inflate_end(&s->zstream);
179
180		✗	return 0;
181			}
182
183			const FFCodec ff_mwsc_decoder = {
184			.p.name = "mwsc",
185			CODEC_LONG_NAME("MatchWare Screen Capture Codec"),
186			.p.type = AVMEDIA_TYPE_VIDEO,
187			.p.id = AV_CODEC_ID_MWSC,
188			.priv_data_size = sizeof(MWSCContext),
189			.init = decode_init,
190			.close = decode_close,
191			FF_CODEC_DECODE_CB(decode_frame),
192			.p.capabilities = AV_CODEC_CAP_DR1,
193			.caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
194			};
195