FFmpeg coverage

Line	Branch	Exec	Source
1			/*
2			* RTP H.263 Depacketizer, RFC 2190
3			* Copyright (c) 2012 Martin Storsjo
4			* Based on the GStreamer H.263 Depayloder:
5			* Copyright 2005 Wim Taymans
6			* Copyright 2007 Edward Hervey
7			* Copyright 2007 Nokia Corporation
8			* Copyright 2007 Collabora Ltd, Philippe Kalaf
9			* Copyright 2010 Mark Nauwelaerts
10			*
11			* This file is part of FFmpeg.
12			*
13			* FFmpeg is free software; you can redistribute it and/or
14			* modify it under the terms of the GNU Lesser General Public
15			* License as published by the Free Software Foundation; either
16			* version 2.1 of the License, or (at your option) any later version.
17			*
18			* FFmpeg is distributed in the hope that it will be useful,
19			* but WITHOUT ANY WARRANTY; without even the implied warranty of
20			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21			* Lesser General Public License for more details.
22			*
23			* You should have received a copy of the GNU Lesser General Public
24			* License along with FFmpeg; if not, write to the Free Software
25			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26			*/
27
28			#include "avformat.h"
29			#include "avio_internal.h"
30			#include "rtpdec_formats.h"
31			#include "libavutil/attributes.h"
32			#include "libavutil/intreadwrite.h"
33			#include "libavcodec/get_bits.h"
34
35			struct PayloadContext {
36			AVIOContext *buf;
37			uint8_t endbyte;
38			int endbyte_bits;
39			uint32_t timestamp;
40			int newformat;
41			};
42
43		✗	static void h263_close_context(PayloadContext *data)
44			{
45		✗	ffio_free_dyn_buf(&data->buf);
46		✗	}
47
48		✗	static int h263_handle_packet(AVFormatContext *ctx, PayloadContext *data,
49			AVStream *st, AVPacket *pkt, uint32_t *timestamp,
50			const uint8_t *buf, int len, uint16_t seq,
51			int flags)
52			{
53			/* Corresponding to header fields in the RFC */
54			int f, p, i, sbit, ebit, src, r;
55			int header_size, ret;
56
57		✗	if (data->newformat)
58		✗	return ff_h263_handle_packet(ctx, data, st, pkt, timestamp, buf, len,
59			seq, flags);
60
61		✗	if (data->buf && data->timestamp != *timestamp) {
62			/* Dropping old buffered, unfinished data */
63		✗	ffio_free_dyn_buf(&data->buf);
64		✗	data->endbyte_bits = 0;
65			}
66
67		✗	if (len < 4) {
68		✗	av_log(ctx, AV_LOG_ERROR, "Too short H.263 RTP packet: %d\n", len);
69		✗	return AVERROR_INVALIDDATA;
70			}
71
72		✗	f = buf[0] & 0x80;
73		✗	p = buf[0] & 0x40;
74		✗	if (!f) {
75			/* Mode A */
76		✗	header_size = 4;
77		✗	i = buf[1] & 0x10;
78		✗	r = ((buf[1] & 0x01) << 3) | ((buf[2] & 0xe0) >> 5);
79		✗	} else if (!p) {
80			/* Mode B */
81		✗	header_size = 8;
82		✗	if (len < header_size) {
83		✗	av_log(ctx, AV_LOG_ERROR,
84			"Too short H.263 RTP packet: %d bytes, %d header bytes\n",
85			len, header_size);
86		✗	return AVERROR_INVALIDDATA;
87			}
88		✗	r = buf[3] & 0x03;
89		✗	i = buf[4] & 0x80;
90			} else {
91			/* Mode C */
92		✗	header_size = 12;
93		✗	if (len < header_size) {
94		✗	av_log(ctx, AV_LOG_ERROR,
95			"Too short H.263 RTP packet: %d bytes, %d header bytes\n",
96			len, header_size);
97		✗	return AVERROR_INVALIDDATA;
98			}
99		✗	r = buf[3] & 0x03;
100		✗	i = buf[4] & 0x80;
101			}
102		✗	sbit = (buf[0] >> 3) & 0x7;
103		✗	ebit = buf[0] & 0x7;
104		✗	src = (buf[1] & 0xe0) >> 5;
105		✗	if (!(buf[0] & 0xf8)) { /* Reserved bits in RFC 2429/4629 are zero */
106		✗	if ((src == 0 || src >= 6) && r) {
107			/* Invalid src for this format, and bits that should be zero
108			* according to RFC 2190 aren't zero. */
109		✗	av_log(ctx, AV_LOG_WARNING,
110			"Interpreting H.263 RTP data as RFC 2429/4629 even though "
111			"signalled with a static payload type.\n");
112		✗	data->newformat = 1;
113		✗	return ff_h263_handle_packet(ctx, data, st, pkt, timestamp, buf,
114			len, seq, flags);
115			}
116			}
117
118		✗	buf += header_size;
119		✗	len -= header_size;
120
121		✗	if (!data->buf) {
122			/* Check the picture start code, only start buffering a new frame
123			* if this is correct */
124		✗	if (len > 4 && AV_RB32(buf) >> 10 == 0x20) {
125		✗	ret = avio_open_dyn_buf(&data->buf);
126		✗	if (ret < 0)
127		✗	return ret;
128		✗	data->timestamp = *timestamp;
129			} else {
130			/* Frame not started yet, skipping */
131		✗	return AVERROR(EAGAIN);
132			}
133			}
134
135		✗	if (data->endbyte_bits || sbit) {
136		✗	if (data->endbyte_bits == sbit) {
137		✗	data->endbyte |= buf[0] & (0xff >> sbit);
138		✗	data->endbyte_bits = 0;
139		✗	buf++;
140		✗	len--;
141		✗	avio_w8(data->buf, data->endbyte);
142			} else {
143			/* Start/end skip bits not matching - missed packets? */
144			GetBitContext gb;
145		✗	ret = init_get_bits(&gb, buf, len*8 - ebit);
146		✗	if (ret < 0)
147		✗	return ret;
148		✗	skip_bits(&gb, sbit);
149		✗	if (data->endbyte_bits) {
150		✗	data->endbyte |= get_bits(&gb, 8 - data->endbyte_bits);
151		✗	avio_w8(data->buf, data->endbyte);
152			}
153		✗	while (get_bits_left(&gb) >= 8)
154		✗	avio_w8(data->buf, get_bits(&gb, 8));
155		✗	data->endbyte_bits = get_bits_left(&gb);
156		✗	if (data->endbyte_bits)
157		✗	data->endbyte = get_bits(&gb, data->endbyte_bits) <<
158		✗	(8 - data->endbyte_bits);
159		✗	ebit = 0;
160		✗	len = 0;
161			}
162			}
163		✗	if (ebit) {
164		✗	if (len > 0)
165		✗	avio_write(data->buf, buf, len - 1);
166		✗	data->endbyte_bits = 8 - ebit;
167		✗	data->endbyte = buf[len - 1] & (0xff << ebit);
168			} else {
169		✗	avio_write(data->buf, buf, len);
170			}
171
172		✗	if (!(flags & RTP_FLAG_MARKER))
173		✗	return AVERROR(EAGAIN);
174
175		✗	if (data->endbyte_bits)
176		✗	avio_w8(data->buf, data->endbyte);
177		✗	data->endbyte_bits = 0;
178
179		✗	ret = ff_rtp_finalize_packet(pkt, &data->buf, st->index);
180		✗	if (ret < 0)
181		✗	return ret;
182		✗	if (!i)
183		✗	pkt->flags |= AV_PKT_FLAG_KEY;
184
185		✗	return 0;
186			}
187
188			const RTPDynamicProtocolHandler ff_h263_rfc2190_dynamic_handler = {
189			.codec_type = AVMEDIA_TYPE_VIDEO,
190			.codec_id = AV_CODEC_ID_H263,
191			.need_parsing = AVSTREAM_PARSE_FULL,
192			.parse_packet = h263_handle_packet,
193			.priv_data_size = sizeof(PayloadContext),
194			.close = h263_close_context,
195			.static_payload_id = 34,
196			};
197