2 * RTMP packet utilities
3 * Copyright (c) 2009 Kostya Shishkov
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #ifndef AVFORMAT_RTMPPKT_H
23 #define AVFORMAT_RTMPPKT_H
27 /** maximum possible number of different RTMP channels */
28 #define RTMP_CHANNELS 65599
31 * channels used to for RTMP packets with different purposes (i.e. data, network
32 * control, remote procedure calls, etc.)
35 RTMP_NETWORK_CHANNEL = 2, ///< channel for network-related messages (bandwidth report, ping, etc)
36 RTMP_SYSTEM_CHANNEL, ///< channel for sending server control messages
37 RTMP_SOURCE_CHANNEL, ///< channel for sending a/v to server
38 RTMP_VIDEO_CHANNEL = 8, ///< channel for video data
39 RTMP_AUDIO_CHANNEL, ///< channel for audio data
43 * known RTMP packet types
45 typedef enum RTMPPacketType {
46 RTMP_PT_CHUNK_SIZE = 1, ///< chunk size change
47 RTMP_PT_BYTES_READ = 3, ///< number of bytes read
48 RTMP_PT_PING, ///< ping
49 RTMP_PT_SERVER_BW, ///< server bandwidth
50 RTMP_PT_CLIENT_BW, ///< client bandwidth
51 RTMP_PT_AUDIO = 8, ///< audio packet
52 RTMP_PT_VIDEO, ///< video packet
53 RTMP_PT_FLEX_STREAM = 15, ///< Flex shared stream
54 RTMP_PT_FLEX_OBJECT, ///< Flex shared object
55 RTMP_PT_FLEX_MESSAGE, ///< Flex shared message
56 RTMP_PT_NOTIFY, ///< some notification
57 RTMP_PT_SHARED_OBJ, ///< shared object
58 RTMP_PT_INVOKE, ///< invoke some stream action
59 RTMP_PT_METADATA = 22, ///< FLV metadata
63 * possible RTMP packet header sizes
66 RTMP_PS_TWELVEBYTES = 0, ///< packet has 12-byte header
67 RTMP_PS_EIGHTBYTES, ///< packet has 8-byte header
68 RTMP_PS_FOURBYTES, ///< packet has 4-byte header
69 RTMP_PS_ONEBYTE ///< packet is really a next chunk of a packet
73 * structure for holding RTMP packets
75 typedef struct RTMPPacket {
76 uint8_t channel_id; ///< RTMP channel ID (nothing to do with audio/video channels though)
77 RTMPPacketType type; ///< packet payload type
78 uint32_t timestamp; ///< packet full timestamp or timestamp increment to the previous one in milliseconds (latter only for media packets)
79 uint32_t extra; ///< probably an additional channel ID used during streaming data
80 uint8_t *data; ///< packet payload
81 int data_size; ///< packet payload size
85 * Creates new RTMP packet with given attributes.
88 * @param channel_id packet channel ID
89 * @param type packet type
90 * @param timestamp packet timestamp
91 * @param size packet size
92 * @return zero on success, negative value otherwise
94 int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
95 int timestamp, int size);
102 void ff_rtmp_packet_destroy(RTMPPacket *pkt);
105 * Reads RTMP packet sent by the server.
107 * @param h reader context
109 * @param chunk_size current chunk size
110 * @param prev_pkt previously read packet headers for all channels
111 * (may be needed for restoring incomplete packet header)
112 * @return zero on success, negative value otherwise
114 int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p,
115 int chunk_size, RTMPPacket *prev_pkt);
118 * Sends RTMP packet to the server.
120 * @param h reader context
121 * @param p packet to send
122 * @param chunk_size current chunk size
123 * @param prev_pkt previously sent packet headers for all channels
124 * (may be used for packet header compressing)
125 * @return zero on success, negative value otherwise
127 int ff_rtmp_packet_write(URLContext *h, RTMPPacket *p,
128 int chunk_size, RTMPPacket *prev_pkt);
131 * @defgroup amffuncs functions used to work with AMF format (which is also used in .flv)
132 * @see amf_* funcs in libavformat/flvdec.c
137 * Calculates number of bytes taken by first AMF entry in data.
139 * @param data input data
140 * @param data_end input buffer end
141 * @return number of bytes used by first AMF entry
143 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end);
146 * Retrieves value of given AMF object field in string form.
148 * @param data AMF object data
149 * @param data_end input buffer end
150 * @param name name of field to retrieve
151 * @param dst buffer for storing result
152 * @param dst_size output buffer size
153 * @return 0 if search and retrieval succeeded, negative value otherwise
155 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
156 const uint8_t *name, uint8_t *dst, int dst_size);
159 * Writes boolean value in AMF format to buffer.
161 * @param dst pointer to the input buffer (will be modified)
162 * @param val value to write
164 void ff_amf_write_bool(uint8_t **dst, int val);
167 * Writes number in AMF format to buffer.
169 * @param dst pointer to the input buffer (will be modified)
170 * @param num value to write
172 void ff_amf_write_number(uint8_t **dst, double num);
175 * Writes string in AMF format to buffer.
177 * @param dst pointer to the input buffer (will be modified)
178 * @param str string to write
180 void ff_amf_write_string(uint8_t **dst, const char *str);
183 * Writes AMF NULL value to buffer.
185 * @param dst pointer to the input buffer (will be modified)
187 void ff_amf_write_null(uint8_t **dst);
190 * Writes marker for AMF object to buffer.
192 * @param dst pointer to the input buffer (will be modified)
194 void ff_amf_write_object_start(uint8_t **dst);
197 * Writes string used as field name in AMF object to buffer.
199 * @param dst pointer to the input buffer (will be modified)
200 * @param str string to write
202 void ff_amf_write_field_name(uint8_t **dst, const char *str);
205 * Writes marker for end of AMF object to buffer.
207 * @param dst pointer to the input buffer (will be modified)
209 void ff_amf_write_object_end(uint8_t **dst);
211 /** @} */ // AMF funcs
213 #endif /* AVFORMAT_RTMPPKT_H */