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// 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
#ifndef QFFMPEGVIDEOENCODERUTILS_P_H
#define QFFMPEGVIDEOENCODERUTILS_P_H
//
// W A R N I N G
// -------------
//
// This file is not part of the Qt API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
#include <QtFFmpegMediaPluginImpl/private/qffmpegdefs_p.h>
#include <QtFFmpegMediaPluginImpl/private/qffmpeghwaccel_p.h>
#include <QtMultimedia/private/qmultimedia_ranges_p.h>
#include <QtCore/qspan.h>
QT_BEGIN_NAMESPACE
namespace QFFmpeg {
// accel == nullptr probes/looks up the plain path (no hw_frames_ctx, i.e. ByteBuffer/MMAP-style
// transport); accel != nullptr probes/looks up the path where the codec is opened with a
// throwaway hw frames context using accel's hw format (Surface/DMABUF-style transport). The two
// can accept different sw formats on real hardware (e.g. Android MediaCodec, V4L2 M2M).
std::vector<AVPixelFormat> encoderPixelFormats(const Codec &, QSize resolution,
const HWAccel *accel);
std::vector<AVPixelFormat> probePixelFormats(const Codec &, QSize resolution,
const HWAccel *accel);
std::optional<AVPixelFormat> findTargetSWFormat(AVPixelFormat sourceSWFormat, const Codec &codec,
const HWAccel &accel, QSize resolution);
AVScore scoreTargetSwFormat(AVPixelFormat source, AVPixelFormat target);
struct ScoredPixelFormat
{
AVPixelFormat format = AV_PIX_FMT_NONE;
AVScore score = NotSuitableAVScore;
};
// sorted by score. accel == nullptr for pure software encoders
std::vector<ScoredPixelFormat> findAndScoreTargetSWFormats(AVPixelFormat sourceSWFormat,
const Codec &, const HWAccel *,
QSize resolution);
std::optional<AVPixelFormat> findTargetFormat(AVPixelFormat sourceSWFormat, const Codec &codec,
const HWAccel *accel, QSize resolution);
AVScore findSWFormatScores(const Codec &codec, AVPixelFormat sourceSWFormat, QSize resolution);
/**
* @brief adjustFrameRate resolves the effective frame rate to negotiate with a codec.
*
* settingsRate is the user-requested rate from QMediaEncoderSettings
* (<= 0 means unset). sourceRate is the source stream's fixed rate
* (<= 0 means variable/unknown).
*
* Target rate priority: settingsRate, if set, always wins. Otherwise sourceRate,
* if fixed, is used. Otherwise, if the codec cannot do variable rate
* (non-empty supportedRates), DefaultVideoFrameRate is used as a
* last-resort target. If the codec can do variable rate (empty
* supportedRates) and neither settingsRate nor sourceRate is set,
* the result stays variable ({0, 1}).
*
* If the codec supports only fixed frame rates (non-null
* supportedRates), the function selects the closest supported rate
* to the resolved preference; otherwise it converts the preference
* directly to an AVRational.
*/
AVRational adjustFrameRate(QSpan<const AVRational> supportedRates, qreal settingsRate,
qreal sourceRate);
/**
* @brief adjustFrameTimeBase gets adjusted timebase by a list of supported frame rates
* and an already adjusted frame rate.
*
* Timebase is the fundamental unit of time (in seconds) in terms
* of which frame timestamps are represented.
* For fixed-fps content (non-null supportedRates, or isFixedRate true),
* timebase should be 1/framerate.
*
* For more information, see AVStream::time_base and AVCodecContext::time_base.
*
* The adjusted time base is supposed to be set to stream and codec context.
*/
AVRational adjustFrameTimeBase(QSpan<const AVRational> supportedRates, AVRational frameRate,
bool isFixedRate);
QSize adjustVideoResolution(const Codec &codec, QSize requestedResolution);
SwsFlags getScaleConversionType(const QSize &sourceSize, const QSize &targetSize);
} // namespace QFFmpeg
QT_END_NAMESPACE
#endif // QFFMPEGVIDEOENCODERUTILS_P_H