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
|
// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qffmpegresampler_p.h"
#include "playbackengine/qffmpegcodec_p.h"
#include "qffmpegmediaformatinfo_p.h"
#include <qloggingcategory.h>
static Q_LOGGING_CATEGORY(qLcResampler, "qt.multimedia.ffmpeg.resampler")
QT_BEGIN_NAMESPACE
using namespace QFFmpeg;
QFFmpegResampler::QFFmpegResampler(const QAudioFormat &inputFormat, const QAudioFormat &outputFormat) :
m_inputFormat(inputFormat), m_outputFormat(outputFormat)
{
Q_ASSERT(inputFormat.isValid());
Q_ASSERT(outputFormat.isValid());
m_resampler =
createResampleContext(AVAudioFormat(m_inputFormat), AVAudioFormat(m_outputFormat));
}
QFFmpegResampler::QFFmpegResampler(const Codec* codec, const QAudioFormat &outputFormat)
: m_outputFormat(outputFormat)
{
Q_ASSERT(codec);
qCDebug(qLcResampler) << "createResampler";
const AVStream *audioStream = codec->stream();
if (!m_outputFormat.isValid())
// want the native format
m_outputFormat = QFFmpegMediaFormatInfo::audioFormatFromCodecParameters(audioStream->codecpar);
m_resampler = createResampleContext(AVAudioFormat(audioStream->codecpar),
AVAudioFormat(m_outputFormat));
}
QFFmpegResampler::~QFFmpegResampler() = default;
QAudioBuffer QFFmpegResampler::resample(const char* data, size_t size)
{
if (!m_inputFormat.isValid())
return {};
return resample(reinterpret_cast<const uint8_t **>(&data),
m_inputFormat.framesForBytes(static_cast<qint32>(size)));
}
QAudioBuffer QFFmpegResampler::resample(const AVFrame *frame)
{
return resample(const_cast<const uint8_t **>(frame->extended_data), frame->nb_samples);
}
QAudioBuffer QFFmpegResampler::resample(const uint8_t **inputData, int inputSamplesCount)
{
const int maxOutSamples = adjustMaxOutSamples(inputSamplesCount);
QByteArray samples(m_outputFormat.bytesForFrames(maxOutSamples), Qt::Uninitialized);
auto *out = reinterpret_cast<uint8_t *>(samples.data());
const int outSamples =
swr_convert(m_resampler.get(), &out, maxOutSamples, inputData, inputSamplesCount);
samples.resize(m_outputFormat.bytesForFrames(outSamples));
qint64 startTime = m_outputFormat.durationForFrames(m_samplesProcessed);
m_samplesProcessed += outSamples;
qCDebug(qLcResampler) << " new frame" << startTime << "in_samples" << inputSamplesCount
<< outSamples << maxOutSamples;
return QAudioBuffer(samples, m_outputFormat, startTime);
}
int QFFmpegResampler::adjustMaxOutSamples(int inputSamplesCount)
{
int maxOutSamples = swr_get_out_samples(m_resampler.get(), inputSamplesCount);
const auto remainingCompensationDistance = m_endCompensationSample - m_samplesProcessed;
if (remainingCompensationDistance > 0 && maxOutSamples > remainingCompensationDistance) {
// If the remaining compensation distance less than output frame,
// the ffmpeg resampler bufferises the rest of frames that makes
// unexpected delays on large frames.
// The hack might cause some compensation bias on large frames,
// however it's not significant for our logic, in fact.
// TODO: probably, it will need some improvements
setSampleCompensation(0, 0);
maxOutSamples = swr_get_out_samples(m_resampler.get(), inputSamplesCount);
}
return maxOutSamples;
}
void QFFmpegResampler::setSampleCompensation(qint32 delta, quint32 distance)
{
const int res = swr_set_compensation(m_resampler.get(), delta, static_cast<int>(distance));
if (res < 0)
qCWarning(qLcResampler) << "swr_set_compensation fail:" << res;
else {
m_sampleCompensationDelta = delta;
m_endCompensationSample = m_samplesProcessed + distance;
}
}
qint32 QFFmpegResampler::activeSampleCompensationDelta() const
{
return m_samplesProcessed < m_endCompensationSample ? m_sampleCompensationDelta : 0;
}
QT_END_NAMESPACE
|
