2 * This file is part of DisOrder.
3 * Copyright (C) 2007 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 /** @file clients/playrtp.h
25 /** @brief Maximum samples per packet we'll support
27 * NB that two channels = two samples in this program.
29 #define MAXSAMPLES 2048
31 /** @brief Number of samples to infill by in one go
33 * This is an upper bound - in practice we expect the underlying audio API to
34 * only ask for a much smaller number of samples in any one go.
36 #define INFILL_SAMPLES (44100 * 2) /* 1s */
38 /** @brief Received packet
40 * Received packets are kept in a binary heap (see @ref pheap) ordered by
44 /** @brief Next packet in @ref next_free_packet or @ref received_packets */
47 /** @brief Number of samples in this packet */
50 /** @brief Timestamp from RTP packet
52 * NB that "timestamps" are really sample counters. Use lt() or lt_packet()
53 * to compare timestamps.
60 * - @ref IDLE - the idle bit was set in the RTP packet
61 * - @ref SILENT - packet is entirely silent
64 /** @brief idle bit set in RTP packet*/
67 /** @brief RTP packet is entirely silent */
70 /** @brief Raw sample data
72 * Only the first @p nsamples samples are defined; the rest is uninitialized
75 uint16_t samples_raw
[MAXSAMPLES
];
78 /** @brief Structure of free packet list */
81 union free_packet
*next
;
84 /** @brief Return true iff \f$a < b\f$ in sequence-space arithmetic
86 * Specifically it returns true if \f$(a-b) mod 2^{32} < 2^{31}\f$.
88 * See also lt_packet().
90 static inline int lt(uint32_t a
, uint32_t b
) {
91 return (uint32_t)(a
- b
) & 0x80000000;
94 /** @brief Return true iff a >= b in sequence-space arithmetic */
95 static inline int ge(uint32_t a
, uint32_t b
) {
99 /** @brief Return true iff a > b in sequence-space arithmetic */
100 static inline int gt(uint32_t a
, uint32_t b
) {
104 /** @brief Return true iff a <= b in sequence-space arithmetic */
105 static inline int le(uint32_t a
, uint32_t b
) {
109 /** @brief Ordering for packets, used by @ref pheap */
110 static inline int lt_packet(const struct packet
*a
, const struct packet
*b
) {
111 return lt(a
->timestamp
, b
->timestamp
);
114 /** @brief Return true if @p p contains @p timestamp
116 * Containment implies that a sample @p timestamp exists within the packet.
118 static inline int contains(const struct packet
*p
, uint32_t timestamp
) {
119 const uint32_t packet_start
= p
->timestamp
;
120 const uint32_t packet_end
= p
->timestamp
+ p
->nsamples
;
122 return (ge(timestamp
, packet_start
)
123 && lt(timestamp
, packet_end
));
127 * @brief Binary heap of packets ordered by timestamp */
128 HEAP_TYPE(pheap
, struct packet
*, lt_packet
);
130 struct packet
*playrtp_new_packet(void);
131 void playrtp_free_packet(struct packet
*p
);
132 void playrtp_fill_buffer(void);
133 struct packet
*playrtp_next_packet(void);
135 extern struct packet
*received_packets
;
136 extern struct packet
**received_tail
;
137 extern pthread_mutex_t receive_lock
;
138 extern pthread_cond_t receive_cond
;
139 extern uint32_t nreceived
;
140 extern struct pheap packets
;
141 extern volatile uint32_t nsamples
;
142 extern uint32_t next_timestamp
;
144 extern pthread_mutex_t lock
;
145 extern pthread_cond_t cond
;
146 extern unsigned minbuffer
;
148 extern int16_t *dump_buffer
;
149 extern size_t dump_index
;
150 extern size_t dump_size
;
152 void playrtp_oss(void), playrtp_alsa(void), playrtp_coreaudio(void);
154 #endif /* PLAYRTP_H */