LiveVideo.h

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/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
 
#ifndef META_OCEAN_MEDIA_LIVE_VIDEO_H
#define META_OCEAN_MEDIA_LIVE_VIDEO_H
 
#include "ocean/media/Media.h"
#include "ocean/media/FrameMedium.h"
#include "ocean/media/LiveMedium.h"
 
namespace Ocean
{
 
namespace Media
{
 
// Forward declaration.
class LiveVideo;
 
/**
 * Definition of a smart medium reference holding a live video object.
 * @see SmartMediumRef, LiveVideo.
 * @ingroup media
 */
typedef SmartMediumRef<LiveVideo> LiveVideoRef;
 
/**
 * This class is the base class for all live videos.
 * @ingroup media
 */
class OCEAN_MEDIA_EXPORT LiveVideo :
    public virtual FrameMedium,
    public virtual LiveMedium
{
    public:
 
        /**
         * Definition of individual control modes.
         * The modes are used for exposure, ISO, and focus.
         */
        enum ControlMode : uint32_t
        {
            /// An invalid control mode.
            CM_INVALID = 0u,
            /// The control is fixed (e.g., because the exposure, ISO, or focus was set manually).
            CM_FIXED,
            /// The control is dynamic (e.g., because auto exposure, ISO, or focus is enabled).
            CM_DYNAMIC
        };
 
        /**
         * Definition of individual stream types.
         */
        enum StreamType : uint32_t
        {
            /// An invalid stream type.
            ST_INVALID = 0u,
            /// A stream composed of individual uncompressed frames with individual pixel formats (e.g., FORMAT_RGB24, FORMAT_YUYV16, etc.).
            ST_FRAME,
            /// A stream composed of Motion JPEG frames.
            ST_MJPEG,
            /// A stream composed of compressed frames with individual codecs (e.g., H264, H265).
            ST_CODEC
        };
 
        /**
         * Definition of a vector holding stream types.
         */
        using StreamTypes = std::vector<StreamType>;
 
        /**
         * Definition of individual codec types.
         */
        enum CodecType : uint32_t
        {
            /// An invalid codec type.
            CT_INVALID = 0u,
            /// Codec using H.264 for encoding or decoding.
            CT_H264,
            /// Codec using H.265 for encoding or decoding.
            CT_H265
        };
 
        /**
         * This class holds the relevant information describing the property of a stream.
         */
        class OCEAN_MEDIA_EXPORT StreamProperty
        {
            public:
 
                /**
                 * Simple helper struct allowing to calculate a hash value for stream property.
                 */
                struct Hash
                {
                    /**
                     * Returns a hash value for a StreamProperty object.
                     * @param streamProperty The object for which the hash will be returned
                     * @return The hash value
                     */
                    inline size_t operator()(const StreamProperty& streamProperty) const;
                };
 
            public:
 
                /**
                 * Default constructor creating an invalid object.
                 */
                StreamProperty() = default;
 
                /**
                 * Creates a new stream property object.
                 * @param streamType The type of the stream
                 * @param width The width of the stream in pixel
                 * @param height The height of the stream in pixel
                 * @param framePixelFormat The pixel format of the stream, invalid if stream type is not ST_FRAME
                 * @param codecType The type of the stream, invalid if stream type is not ST_CODEC
                 */
                StreamProperty(const StreamType streamType, const unsigned int width, unsigned int height, const FrameType::PixelFormat framePixelFormat, const CodecType codecType);
 
                /**
                 * Returns whether this configuration object holds a valid configuration.
                 * The configuration is valid if a valid stream type and a valid image resolution is defined.
                 * @return True, if so
                 */
                inline bool isValid() const;
 
                /**
                 * Returns whether this configuration object holds the same configuration as the given one.
                 * @param right The configuration object to compare
                 * @return True, if so
                 */
                bool operator==(const StreamProperty& right) const;
 
            public:
 
                /// The type of the stream.
                StreamType streamType_ = ST_INVALID;
 
                /// The width of the stream in pixel.
                unsigned int width_ = 0u;
 
                /// The height of the stream in pixel.
                unsigned int height_ = 0u;
 
                /// The pixel format of the stream, only valid if the stream type is ST_FRAME.
                FrameType::PixelFormat framePixelFormat_ = FrameType::FORMAT_UNDEFINED;
 
                /// The codec of the stream, only valid if the stream type is ST_CODEC.
                CodecType codecType_ = CT_INVALID;
        };
 
        /**
         * This class holds the relevant information describing a video stream configuration.
         */
        class OCEAN_MEDIA_EXPORT StreamConfiguration : public StreamProperty
        {
            public:
 
                /**
                 * Default constructor creating an invalid object.
                 */
                StreamConfiguration() = default;
 
                /**
                 * Creates a new stream configuration object.
                 * @param streamProperty The property of the stream
                 * @param frameRates The frame rates of the stream in Hz
                 */
                StreamConfiguration(const StreamProperty& streamProperty, std::vector<double>&& frameRates);
 
                /**
                 * Creates a new stream configuration object.
                 * @param streamType The type of the stream
                 * @param width The width of the stream in pixel
                 * @param height The height of the stream in pixel
                 * @param frameRates The frame rates of the stream in Hz
                 * @param framePixelFormat The pixel format of the stream, invalid if stream type is not ST_FRAME
                 * @param codecType The type of the stream, invalid if stream type is not ST_CODEC
                 */
                StreamConfiguration(const StreamType streamType, const unsigned int width, unsigned int height, std::vector<double>&& frameRates, const FrameType::PixelFormat framePixelFormat, const CodecType codecType);
 
                /**
                 * Returns a string containing the readable information of this stream configuration.
                 * @return The readable information of this stream configuration
                 */
                std::string toString() const;
 
            public:
 
                /// The frame rates of the stream in Hz.
                std::vector<double> frameRates_;
        };
 
        /**
         * Definition of a vector holding stream configurations.
         */
        using StreamConfigurations = std::vector<StreamConfiguration>;
 
    public:
 
        /**
         * Returns the supported stream types.
         * @return The types of all supported streams, empty if this object does not allow (or does not need) to select the stream type.
         */
        virtual StreamTypes supportedStreamTypes() const;
 
        /**
         * Returns the supported stream configurations for a given stream type.
         * @param streamType The type of the stream for which the supported stream configurations will be returned, ST_INVALID to return all stream configurations for all stream types
         * @return The supported stream configurations
         */
        virtual StreamConfigurations supportedStreamConfigurations(const StreamType streamType = ST_INVALID) const;
 
        /**
         * Returns the current exposure duration of this device.
         * @param minDuration Optional resulting minimal duration to set, in seconds, with range (0, infinity), -1 if unknown
         * @param maxDuration Optional resulting maximal duration to set, in seconds, with range [minDuration, infinity), -1 if unknown
         * @param exposureMode Optional resulting exposure mode, nullptr if not of interest
         * @return The duration in seconds, with range [minDuration, maxDuration], -1 if unknown
         * @see setExposureDuration().
         */
        virtual double exposureDuration(double* minDuration = nullptr, double* maxDuration = nullptr, ControlMode* exposureMode = nullptr) const;
 
        /**
         * Returns the current ISO of this device.
         * @param minISO Optional resulting minimal ISO to set, with range (0, infinity), -1 if unknown
         * @param maxISO Optional resulting maximal ISO to set, with range (0, infinity), -1 if unknown
         * @param isoMode Optional resulting ISO mode, nullptr if not of interest
         * @return The current ISO, with range [minISO, maxISO], -1 if unknown
         */
        virtual float iso(float* minISO = nullptr, float* maxISO = nullptr, ControlMode* isoMode = nullptr) const;
 
        /**
         * Returns the current focus of this device.
         * @return The device's focus, with range [0, 1] with 0 shortest distance and 1 furthest distance
         * @param focusMode Optional resulting focus mode, nullptr if not of interest
         */
        virtual float focus(ControlMode* focusMode = nullptr) const;
 
        /**
         * Sets the preferred stream type.
         * There is no guarantee that the device will use this stream type.
         * @param streamType The preferred stream type to be set, must be valid
         * @return True, if succeeded
         * @see setPreferredStreamConfiguration().
         */
        virtual bool setPreferredStreamType(const StreamType streamType);
 
        /**
         * Sets the preferred stream configuration.
         * Using this function will forward some settings to the underlying FrameMedium object via setPreferredFrameDimension(), setPreferredFramePixelFormat(), and setPreferredFrameFrequency().
         * There is no guarantee that the device will use this stream type.
         * @param streamConfiguration The preferred stream configuration to be set, must be valid
         * @return True, if succeeded
         * @see setPreferredStreamType(), FrameMedium::setPreferredFrameDimension(), FrameMedium::setPreferredFramePixelFormat(), and FrameMedium::setPreferredFrameFrequency()
         */
        virtual bool setPreferredStreamConfiguration(const StreamConfiguration& streamConfiguration);
 
        /**
         * Sets the exposure duration of this device.
         * @param duration The exposure duration to be set, in seconds, with range (0, infinity), 0 for auto exposure, -1 for a one-time auto exposure
         * @param allowShorterExposure True, to allow shorter exposure durations than the specified duration; False, to enforce the specified duration; Ignored if auto exposure is used
         * @return True, if succeeded
         * @see exposureDuration().
         */
        virtual bool setExposureDuration(const double duration, const bool allowShorterExposure = false);
 
        /**
         * Sets the ISO of this device.
         * @param iso The ISO to be set, with range (0, infinity), -1 for auto ISO
         * @return True, if succeeded
         * @see iso().
         */
        virtual bool setISO(const float iso);
 
        /**
         * Sets the focus of this device.
         * @param position The focus position to be set, with range [0, 1] with 0 shortest distance and 1 furthest distance, -1 for auto focus
         * @return True, if succeeded
         * @see focus().
         */
        virtual bool setFocus(const float position);
 
        /**
         * Translates a control mode to a string.
         * @param controlMode The control mode to translate
         * @return The translated string, 'Invalid' if the control mode is invalid or unknown
         */
        static std::string translateControlMode(const ControlMode controlMode);
 
        /**
         * Translates a stream type to a string.
         * @param streamType The stream type to be translated
         * @return The translated string, 'Invalid' if the stream type is invalid or unknown
         */
        static std::string translateStreamType(const StreamType streamType);
 
        /**
         * Translates a codec type to a string.
         * @param codecType The stream type to be translated
         * @return The translated string, 'Invalid' if the codec type is invalid or unknown
         */
        static std::string translateCodecType(const CodecType codecType);
 
    protected:
 
        /**
         * Creates a new live video source by a given url.
         * @param url Url of the live video source
         */
        explicit LiveVideo(const std::string& url);
};
 
inline size_t LiveVideo::StreamProperty::Hash::operator()(const StreamProperty& streamProperty) const
{
    size_t seed = std::hash<StreamType>{}(streamProperty.streamType_);
    seed ^= std::hash<unsigned int>{}(streamProperty.width_) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
    seed ^= std::hash<unsigned int>{}(streamProperty.height_) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
    seed ^= std::hash<FrameType::PixelFormat>{}(streamProperty.framePixelFormat_) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
    seed ^= std::hash<CodecType>{}(streamProperty.codecType_) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
 
    return seed;
}
 
inline bool LiveVideo::StreamProperty::isValid() const
{
    return streamType_ != ST_INVALID && width_ > 0u && height_ > 0u;
}
 
}
 
}
 
#endif // META_OCEAN_MEDIA_LIVE_VIDEO_H