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 int 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
79 uint32_t ts_delta; ///< timestamp increment to the previous one in milliseconds (latter only for media packets)
80 uint32_t extra; ///< probably an additional channel ID used during streaming data
81 uint8_t *data; ///< packet payload
82 int data_size; ///< packet payload size
86 * Create new RTMP packet with given attributes.
89 * @param channel_id packet channel ID
90 * @param type packet type
91 * @param timestamp packet timestamp
92 * @param size packet size
93 * @return zero on success, negative value otherwise
95 int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
96 int timestamp, int size);
103 void ff_rtmp_packet_destroy(RTMPPacket *pkt);
106 * Read RTMP packet sent by the server.
108 * @param h reader context
110 * @param chunk_size current chunk size
111 * @param prev_pkt previously read packet headers for all channels
112 * (may be needed for restoring incomplete packet header)
113 * @return number of bytes read on success, negative value otherwise
115 int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p,
116 int chunk_size, RTMPPacket *prev_pkt);
119 * Send RTMP packet to the server.
121 * @param h reader context
122 * @param p packet to send
123 * @param chunk_size current chunk size
124 * @param prev_pkt previously sent packet headers for all channels
125 * (may be used for packet header compressing)
126 * @return number of bytes written on success, negative value otherwise
128 int ff_rtmp_packet_write(URLContext *h, RTMPPacket *p,
129 int chunk_size, RTMPPacket *prev_pkt);
132 * Print information and contents of RTMP packet.
134 * @param ctx output context
135 * @param p packet to dump
137 void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p);
140 * @defgroup amffuncs functions used to work with AMF format (which is also used in .flv)
141 * @see amf_* funcs in libavformat/flvdec.c
146 * Calculate number of bytes taken by first AMF entry in data.
148 * @param data input data
149 * @param data_end input buffer end
150 * @return number of bytes used by first AMF entry
152 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end);
155 * Retrieve value of given AMF object field in string form.
157 * @param data AMF object data
158 * @param data_end input buffer end
159 * @param name name of field to retrieve
160 * @param dst buffer for storing result
161 * @param dst_size output buffer size
162 * @return 0 if search and retrieval succeeded, negative value otherwise
164 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
165 const uint8_t *name, uint8_t *dst, int dst_size);
168 * Write boolean value in AMF format to buffer.
170 * @param dst pointer to the input buffer (will be modified)
171 * @param val value to write
173 void ff_amf_write_bool(uint8_t **dst, int val);
176 * Write number in AMF format to buffer.
178 * @param dst pointer to the input buffer (will be modified)
179 * @param num value to write
181 void ff_amf_write_number(uint8_t **dst, double num);
184 * Write string in AMF format to buffer.
186 * @param dst pointer to the input buffer (will be modified)
187 * @param str string to write
189 void ff_amf_write_string(uint8_t **dst, const char *str);
192 * Write AMF NULL value to buffer.
194 * @param dst pointer to the input buffer (will be modified)
196 void ff_amf_write_null(uint8_t **dst);
199 * Write marker for AMF object to buffer.
201 * @param dst pointer to the input buffer (will be modified)
203 void ff_amf_write_object_start(uint8_t **dst);
206 * Write string used as field name in AMF object to buffer.
208 * @param dst pointer to the input buffer (will be modified)
209 * @param str string to write
211 void ff_amf_write_field_name(uint8_t **dst, const char *str);
214 * Write marker for end of AMF object to buffer.
216 * @param dst pointer to the input buffer (will be modified)
218 void ff_amf_write_object_end(uint8_t **dst);
220 /** @} */ // AMF funcs
222 #endif /* AVFORMAT_RTMPPKT_H */