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
|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Copyright (C) 2021, Ideas on Board Oy
*
* image.cpp - Multi-planar image with access to pixel data
*/
#include "image.h"
#include <assert.h>
#include <errno.h>
#include <iostream>
#include <map>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
using namespace libcamera;
std::unique_ptr<Image> Image::fromFrameBuffer(const FrameBuffer *buffer, MapMode mode)
{
std::unique_ptr<Image> image{ new Image() };
assert(!buffer->planes().empty());
int mmapFlags = 0;
if (mode & MapMode::ReadOnly)
mmapFlags |= PROT_READ;
if (mode & MapMode::WriteOnly)
mmapFlags |= PROT_WRITE;
struct MappedBufferInfo {
uint8_t *address = nullptr;
size_t mapLength = 0;
size_t dmabufLength = 0;
};
std::map<int, MappedBufferInfo> mappedBuffers;
for (const FrameBuffer::Plane &plane : buffer->planes()) {
const int fd = plane.fd.get();
if (mappedBuffers.find(fd) == mappedBuffers.end()) {
const size_t length = lseek(fd, 0, SEEK_END);
mappedBuffers[fd] = MappedBufferInfo{ nullptr, 0, length };
}
const size_t length = mappedBuffers[fd].dmabufLength;
if (plane.offset > length ||
plane.offset + plane.length > length) {
std::cerr << "plane is out of buffer: buffer length="
<< length << ", plane offset=" << plane.offset
<< ", plane length=" << plane.length
<< std::endl;
return nullptr;
}
size_t &mapLength = mappedBuffers[fd].mapLength;
mapLength = std::max(mapLength,
static_cast<size_t>(plane.offset + plane.length));
}
for (const FrameBuffer::Plane &plane : buffer->planes()) {
const int fd = plane.fd.get();
auto &info = mappedBuffers[fd];
if (!info.address) {
void *address = mmap(nullptr, info.mapLength, mmapFlags,
MAP_SHARED, fd, 0);
if (address == MAP_FAILED) {
int error = -errno;
std::cerr << "Failed to mmap plane: "
<< strerror(-error) << std::endl;
return nullptr;
}
info.address = static_cast<uint8_t *>(address);
image->maps_.emplace_back(info.address, info.mapLength);
}
image->planes_.emplace_back(info.address + plane.offset, plane.length);
}
return image;
}
Image::Image() = default;
Image::~Image()
{
for (Span<uint8_t> &map : maps_)
munmap(map.data(), map.size());
}
unsigned int Image::numPlanes() const
{
return planes_.size();
}
Span<uint8_t> Image::data(unsigned int plane)
{
assert(plane <= planes_.size());
return planes_[plane];
}
Span<const uint8_t> Image::data(unsigned int plane) const
{
assert(plane <= planes_.size());
return planes_[plane];
}
|
