1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
/* SPDX-License-Identifier: BSD-2-Clause */
/*
* Copyright (C) 2020, Raspberry Pi (Trading) Ltd.
*
* mjpeg_encoder.cpp - mjpeg video encoder.
*/
#include <chrono>
#include <iostream>
#include <pthread.h>
#include <jpeglib.h>
#include <libcamera/libcamera.h>
#include "mjpeg_encoder.hpp"
#if JPEG_LIB_VERSION_MAJOR > 9 || (JPEG_LIB_VERSION_MAJOR == 9 && JPEG_LIB_VERSION_MINOR >= 4)
typedef size_t jpeg_mem_len_t;
#else
typedef unsigned long jpeg_mem_len_t;
#endif
MjpegEncoder::MjpegEncoder()
: abortEncode_(false), abortOutput_(false), index_(0)
{
output_thread_ = std::thread(&MjpegEncoder::outputThread, this);
for (int i = 0; i < NUM_ENC_THREADS; i++)
encode_thread_[i] = std::thread(std::bind(&MjpegEncoder::encodeThread, this, i));
}
MjpegEncoder::~MjpegEncoder()
{
abortEncode_ = true;
for (int i = 0; i < NUM_ENC_THREADS; i++)
encode_thread_[i].join();
abortOutput_ = true;
output_thread_.join();
}
void MjpegEncoder::EncodeBuffer(void *mem, void *dest, unsigned int size,
StreamInfo const &info, int64_t timestamp_us,
unsigned int cookie)
{
std::lock_guard<std::mutex> lock(encode_mutex_);
EncodeItem item = { mem, dest, size, info, timestamp_us, index_++, cookie };
encode_queue_.push(item);
encode_cond_var_.notify_all();
}
void MjpegEncoder::encodeJPEG(struct jpeg_compress_struct &cinfo, EncodeItem &item,
uint8_t *&encoded_buffer, size_t &buffer_len)
{
cinfo.image_width = item.info.width;
cinfo.image_height = item.info.height;
cinfo.input_components = 3;
cinfo.in_color_space = JCS_YCbCr;
cinfo.restart_interval = 0;
jpeg_set_defaults(&cinfo);
cinfo.raw_data_in = TRUE;
jpeg_set_quality(&cinfo, 50, TRUE);
jpeg_mem_len_t jpeg_mem_len = buffer_len;
jpeg_mem_dest(&cinfo, &encoded_buffer, &jpeg_mem_len);
jpeg_start_compress(&cinfo, TRUE);
int stride2 = item.info.stride / 2;
uint8_t *Y = (uint8_t *)item.mem;
uint8_t *U = (uint8_t *)Y + item.info.stride * item.info.height;
uint8_t *V = (uint8_t *)U + stride2 * (item.info.height / 2);
uint8_t *Y_max = U - item.info.stride;
uint8_t *U_max = V - stride2;
uint8_t *V_max = U_max + stride2 * (item.info.height / 2);
JSAMPROW y_rows[16];
JSAMPROW u_rows[8];
JSAMPROW v_rows[8];
for (uint8_t *Y_row = Y, *U_row = U, *V_row = V; cinfo.next_scanline < item.info.height;)
{
for (int i = 0; i < 16; i++, Y_row += item.info.stride)
y_rows[i] = std::min(Y_row, Y_max);
for (int i = 0; i < 8; i++, U_row += stride2, V_row += stride2) {
u_rows[i] = std::min(U_row, U_max);
v_rows[i] = std::min(V_row, V_max);
}
JSAMPARRAY rows[] = { y_rows, u_rows, v_rows };
jpeg_write_raw_data(&cinfo, rows, 16);
}
jpeg_finish_compress(&cinfo);
buffer_len = jpeg_mem_len;
}
void MjpegEncoder::encodeThread(int num)
{
struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr;
EncodeItem encode_item;
uint32_t frames = 0;
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_compress(&cinfo);
while (true)
{
{
std::unique_lock<std::mutex> lock(encode_mutex_);
while (true)
{
using namespace std::chrono_literals;
if (abortEncode_ && encode_queue_.empty())
{
jpeg_destroy_compress(&cinfo);
return;
}
if (!encode_queue_.empty())
{
encode_item = encode_queue_.front();
encode_queue_.pop();
break;
}
else
encode_cond_var_.wait_for(lock, 200ms);
}
}
uint8_t *encoded_buffer = (uint8_t *)encode_item.dest;
size_t buffer_len = encode_item.size;
encodeJPEG(cinfo, encode_item, encoded_buffer, buffer_len);
frames++;
/*
* Don't return buffers until the output thread as that's where
* they're in order again.
*
* We push this encoded buffer to another thread so that our
* application can take its time with the data without blocking
* the encode process.
*/
OutputItem output_item = {
encoded_buffer,
buffer_len,
encode_item.timestamp_us,
encode_item.index,
encode_item.cookie
};
std::lock_guard<std::mutex> lock(output_mutex_);
output_queue_[num].push(output_item);
output_cond_var_.notify_one();
}
}
void MjpegEncoder::outputThread()
{
OutputItem item;
uint64_t index = 0;
while (true)
{
{
std::unique_lock<std::mutex> lock(output_mutex_);
while (true)
{
using namespace std::chrono_literals;
/*
* We look for the thread that's completed the
* frame we want next. If we don't find it, we
* wait.
*
* Must also check for an abort signal and if
* set, all queues must be empty. This is done
* first to ensure all frame callbacks have a
* chance to run.
*/
bool abort = abortOutput_ ? true : false;
for (auto &q : output_queue_)
{
if (abort && !q.empty())
abort = false;
if (!q.empty() && q.front().index == index)
{
item = q.front();
q.pop();
goto got_item;
}
}
if (abort)
return;
output_cond_var_.wait_for(lock, 200ms);
}
}
got_item:
output_ready_callback_(item.mem, item.bytes_used, item.timestamp_us, item.cookie);
index++;
}
}
StreamInfo MjpegEncoder::getStreamInfo(libcamera::Stream *stream)
{
libcamera::StreamConfiguration const &cfg = stream->configuration();
StreamInfo info;
info.width = cfg.size.width;
info.height = cfg.size.height;
info.stride = cfg.stride;
info.pixel_format = cfg.pixelFormat;
info.colour_space = cfg.colorSpace;
return info;
}
|
