qmediaformat.cpp

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// Copyright (C) 2021 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 "qmediaformat.h"
#include "private/qplatformmediaintegration_p.h"
#include "private/qplatformmediaformatinfo_p.h"
#include <QtCore/qmimedatabase.h>
 
QT_BEGIN_NAMESPACE
 
 
namespace {
 
const char *mimeTypeForFormat[QMediaFormat::LastFileFormat + 2] =
{
    "",
    "video/x-ms-wmv",
    "video/x-msvideo",
    "video/x-matroska",
    "video/mp4",
    "video/ogg",
    "video/quicktime",
    "video/webm",
    // Audio Formats
    "audio/mp4",
    "audio/aac",
    "audio/x-ms-wma",
    "audio/mpeg",
    "audio/flac",
    "audio/wav"
};
 
constexpr QMediaFormat::FileFormat videoFormatPriorityList[] =
{
    QMediaFormat::MPEG4,
    QMediaFormat::QuickTime,
    QMediaFormat::AVI,
    QMediaFormat::WebM,
    QMediaFormat::WMV,
    QMediaFormat::Matroska,
    QMediaFormat::Ogg,
    QMediaFormat::UnspecifiedFormat
};
 
constexpr QMediaFormat::FileFormat audioFormatPriorityList[] =
{
    QMediaFormat::Mpeg4Audio,
    QMediaFormat::MP3,
    QMediaFormat::WMA,
    QMediaFormat::FLAC,
    QMediaFormat::Wave,
    QMediaFormat::UnspecifiedFormat
};
 
constexpr QMediaFormat::AudioCodec audioPriorityList[] =
{
    QMediaFormat::AudioCodec::AAC,
    QMediaFormat::AudioCodec::MP3,
    QMediaFormat::AudioCodec::AC3,
    QMediaFormat::AudioCodec::Opus,
    QMediaFormat::AudioCodec::EAC3,
    QMediaFormat::AudioCodec::DolbyTrueHD,
    QMediaFormat::AudioCodec::WMA,
    QMediaFormat::AudioCodec::FLAC,
    QMediaFormat::AudioCodec::Vorbis,
    QMediaFormat::AudioCodec::Wave,
    QMediaFormat::AudioCodec::Unspecified
};
 
constexpr QMediaFormat::VideoCodec videoPriorityList[] =
{
    QMediaFormat::VideoCodec::H265,
    QMediaFormat::VideoCodec::VP9,
    QMediaFormat::VideoCodec::H264,
    QMediaFormat::VideoCodec::AV1,
    QMediaFormat::VideoCodec::VP8,
    QMediaFormat::VideoCodec::WMV,
    QMediaFormat::VideoCodec::Theora,
    QMediaFormat::VideoCodec::MPEG4,
    QMediaFormat::VideoCodec::MPEG2,
    QMediaFormat::VideoCodec::MPEG1,
    QMediaFormat::VideoCodec::MotionJPEG,
};
 
}
 
class QMediaFormatPrivate : public QSharedData
{};
 
QT_DEFINE_QESDP_SPECIALIZATION_DTOR(QMediaFormatPrivate);
 
// these are non inline to make a possible future addition of a d pointer binary compatible
 
QMediaFormat::QMediaFormat(FileFormat format)
    : fmt(format)
{
}
 
QMediaFormat::~QMediaFormat() = default;
 
QMediaFormat::QMediaFormat(const QMediaFormat &other) noexcept = default;
 
QMediaFormat &QMediaFormat::operator=(const QMediaFormat &other) noexcept = default;
 
// Properties
bool QMediaFormat::isSupported(ConversionMode mode) const
{
    return QPlatformMediaIntegration::instance()->formatInfo()->isSupported(*this, mode);
}
 
QMimeType QMediaFormat::mimeType() const
{
    return QMimeDatabase().mimeTypeForName(QString::fromLatin1(mimeTypeForFormat[fmt + 1]));
}
 
static QPlatformMediaFormatInfo *formatInfo()
{
    QPlatformMediaFormatInfo *result = nullptr;
    if (auto *pi = QPlatformMediaIntegration::instance())
        result = pi->formatInfo();
    return result;
}
 
QList<QMediaFormat::FileFormat> QMediaFormat::supportedFileFormats(QMediaFormat::ConversionMode m)
{
    auto *fi = formatInfo();
    return fi != nullptr ? fi->supportedFileFormats(*this, m) : QList<QMediaFormat::FileFormat>{};
}
 
QList<QMediaFormat::VideoCodec> QMediaFormat::supportedVideoCodecs(QMediaFormat::ConversionMode m)
{
    auto *fi = formatInfo();
    return fi != nullptr ? fi->supportedVideoCodecs(*this, m) : QList<QMediaFormat::VideoCodec>{};
}
 
QList<QMediaFormat::AudioCodec> QMediaFormat::supportedAudioCodecs(QMediaFormat::ConversionMode m)
{
    auto *fi = formatInfo();
    return fi != nullptr ? fi->supportedAudioCodecs(*this, m) : QList<QMediaFormat::AudioCodec>{};
}
 
QString QMediaFormat::fileFormatName(QMediaFormat::FileFormat fileFormat)
{
    constexpr const char *descriptions[QMediaFormat::LastFileFormat + 2] = {
        "Unspecified",
        "WMV",
        "AVI",
        "Matroska",
        "MPEG-4",
        "Ogg",
        "QuickTime",
        "WebM",
        // Audio Formats
        "MPEG-4 Audio",
        "AAC",
        "WMA",
        "MP3",
        "FLAC",
        "Wave"
    };
    return QString::fromUtf8(descriptions[int(fileFormat) + 1]);
}
 
QString QMediaFormat::audioCodecName(QMediaFormat::AudioCodec codec)
{
    constexpr const char *descriptions[] = {
        "Invalid",
        "MP3",
        "AAC",
        "AC3",
        "EAC3",
        "FLAC",
        "DolbyTrueHD",
        "Opus",
        "Vorbis",
        "Wave",
        "WMA",
        "ALAC",
    };
    return QString::fromUtf8(descriptions[int(codec) + 1]);
}
 
QString QMediaFormat::videoCodecName(QMediaFormat::VideoCodec codec)
{
    constexpr const char *descriptions[] = {
        "Invalid",
        "MPEG1",
        "MPEG2",
        "MPEG4",
        "H264",
        "H265",
        "VP8",
        "VP9",
        "AV1",
        "Theora",
        "WMV",
        "MotionJPEG"
    };
    return QString::fromUtf8(descriptions[int(codec) + 1]);
}
 
QString QMediaFormat::fileFormatDescription(QMediaFormat::FileFormat fileFormat)
{
    constexpr const char *descriptions[QMediaFormat::LastFileFormat + 2] = {
        "Unspecified File Format",
        "Windows Media Video",
        "Audio Video Interleave",
        "Matroska Multimedia Container",
        "MPEG-4 Video Container",
        "Ogg",
        "QuickTime Container",
        "WebM",
        // Audio Formats
        "MPEG-4 Audio",
        "AAC",
        "Windows Media Audio",
        "MP3",
        "Free Lossless Audio Codec (FLAC)",
        "Wave File"
    };
    return QString::fromUtf8(descriptions[int(fileFormat) + 1]);
}
 
QString QMediaFormat::audioCodecDescription(QMediaFormat::AudioCodec codec)
{
    constexpr const char *descriptions[] = {
        "Unspecified Audio Codec",
        "MP3",
        "Advanced Audio Codec (AAC)",
        "Dolby Digital (AC3)",
        "Dolby Digital Plus (E-AC3)",
        "Free Lossless Audio Codec (FLAC)",
        "Dolby True HD",
        "Opus",
        "Vorbis",
        "Wave",
        "Windows Media Audio",
        "Apple Lossless Audio Codec (ALAC)",
    };
    return QString::fromUtf8(descriptions[int(codec) + 1]);
}
 
QString QMediaFormat::videoCodecDescription(QMediaFormat::VideoCodec codec)
{
    constexpr const char *descriptions[] = {
        "Unspecified Video Codec",
        "MPEG-1 Video",
        "MPEG-2 Video",
        "MPEG-4 Video",
        "H.264",
        "H.265",
        "VP8",
        "VP9",
        "AV1",
        "Theora",
        "Windows Media Video",
        "MotionJPEG"
    };
    return QString::fromUtf8(descriptions[int(codec) + 1]);
}
 
bool QMediaFormat::operator==(const QMediaFormat &other) const
{
    Q_ASSERT(!d);
    return fmt == other.fmt &&
            audio == other.audio &&
           video == other.video;
}
 
void QMediaFormat::resolveForEncoding(ResolveFlags flags)
{
    const bool requiresVideo = (flags & ResolveFlags::RequiresVideo) != 0;
 
    if (!requiresVideo)
        video = VideoCodec::Unspecified;
 
    // need to adjust the format. Priority is given first to file format, then video codec, then audio codec
 
    QMediaFormat nullFormat;
    auto supportedFormats = nullFormat.supportedFileFormats(QMediaFormat::Encode);
    auto supportedAudioCodecs = nullFormat.supportedAudioCodecs(QMediaFormat::Encode);
    auto supportedVideoCodecs = nullFormat.supportedVideoCodecs(QMediaFormat::Encode);
 
    auto bestSupportedFileFormat = [&](QMediaFormat::AudioCodec audio = QMediaFormat::AudioCodec::Unspecified,
                                       QMediaFormat::VideoCodec video = QMediaFormat::VideoCodec::Unspecified)
    {
        QMediaFormat f;
        f.setAudioCodec(audio);
        f.setVideoCodec(video);
        auto supportedFormats = f.supportedFileFormats(QMediaFormat::Encode);
        auto *list = (flags == NoFlags) ? audioFormatPriorityList : videoFormatPriorityList;
        while (*list != QMediaFormat::UnspecifiedFormat) {
            if (supportedFormats.contains(*list))
                break;
            ++list;
        }
        return *list;
    };
 
    // reset format if it does not support video when video is required
    if (requiresVideo && this->supportedVideoCodecs(QMediaFormat::Encode).isEmpty())
        fmt = QMediaFormat::UnspecifiedFormat;
 
    // reset non supported formats and codecs
    if (!supportedFormats.contains(fmt))
        fmt = QMediaFormat::UnspecifiedFormat;
    if (!supportedAudioCodecs.contains(audio))
        audio = QMediaFormat::AudioCodec::Unspecified;
    if (!requiresVideo || !supportedVideoCodecs.contains(video))
        video = QMediaFormat::VideoCodec::Unspecified;
 
    if (requiresVideo) {
        // try finding a file format that is supported
        if (fmt == QMediaFormat::UnspecifiedFormat)
            fmt = bestSupportedFileFormat(audio, video);
        // try without the audio codec
        if (fmt == QMediaFormat::UnspecifiedFormat)
            fmt = bestSupportedFileFormat(QMediaFormat::AudioCodec::Unspecified, video);
    }
    // try without the video codec
    if (fmt == QMediaFormat::UnspecifiedFormat)
        fmt = bestSupportedFileFormat(audio);
    // give me a format that's supported
    if (fmt == QMediaFormat::UnspecifiedFormat)
        fmt = bestSupportedFileFormat();
    // still nothing? Give up
    if (fmt == QMediaFormat::UnspecifiedFormat) {
        *this = {};
        return;
    }
 
    // find a working video codec
    if (requiresVideo) {
        // reset the audio codec, so that we won't throw away the video codec
        // if it is supported (choosing the specified video codec has higher
        // priority than the specified audio codec)
        auto a = audio;
        audio = QMediaFormat::AudioCodec::Unspecified;
        auto videoCodecs = this->supportedVideoCodecs(QMediaFormat::Encode);
        if (!videoCodecs.contains(video)) {
            // not supported, try to find a replacement
            auto *list = videoPriorityList;
            while (*list != QMediaFormat::VideoCodec::Unspecified) {
                if (videoCodecs.contains(*list))
                    break;
                ++list;
            }
            video = *list;
        }
        audio = a;
    } else {
        video = QMediaFormat::VideoCodec::Unspecified;
    }
 
    // and a working audio codec
    auto audioCodecs = this->supportedAudioCodecs(QMediaFormat::Encode);
    if (!audioCodecs.contains(audio)) {
        auto *list = audioPriorityList;
        while (*list != QMediaFormat::AudioCodec::Unspecified) {
            if (audioCodecs.contains(*list))
                break;
            ++list;
        }
        audio = *list;
    }
}
 
QT_END_NAMESPACE
 
#include "moc_qmediaformat.cpp"