duckstation

hwcontext.h (24079B)

---

 /*
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #ifndef AVUTIL_HWCONTEXT_H
 #define AVUTIL_HWCONTEXT_H
 
 #include "buffer.h"
 #include "frame.h"
 #include "log.h"
 #include "pixfmt.h"
 
 enum AVHWDeviceType {
     AV_HWDEVICE_TYPE_NONE,
     AV_HWDEVICE_TYPE_VDPAU,
     AV_HWDEVICE_TYPE_CUDA,
     AV_HWDEVICE_TYPE_VAAPI,
     AV_HWDEVICE_TYPE_DXVA2,
     AV_HWDEVICE_TYPE_QSV,
     AV_HWDEVICE_TYPE_VIDEOTOOLBOX,
     AV_HWDEVICE_TYPE_D3D11VA,
     AV_HWDEVICE_TYPE_DRM,
     AV_HWDEVICE_TYPE_OPENCL,
     AV_HWDEVICE_TYPE_MEDIACODEC,
     AV_HWDEVICE_TYPE_VULKAN,
     AV_HWDEVICE_TYPE_D3D12VA,
 };
 
 /**
  * This struct aggregates all the (hardware/vendor-specific) "high-level" state,
  * i.e. state that is not tied to a concrete processing configuration.
  * E.g., in an API that supports hardware-accelerated encoding and decoding,
  * this struct will (if possible) wrap the state that is common to both encoding
  * and decoding and from which specific instances of encoders or decoders can be
  * derived.
  *
  * This struct is reference-counted with the AVBuffer mechanism. The
  * av_hwdevice_ctx_alloc() constructor yields a reference, whose data field
  * points to the actual AVHWDeviceContext. Further objects derived from
  * AVHWDeviceContext (such as AVHWFramesContext, describing a frame pool with
  * specific properties) will hold an internal reference to it. After all the
  * references are released, the AVHWDeviceContext itself will be freed,
  * optionally invoking a user-specified callback for uninitializing the hardware
  * state.
  */
 typedef struct AVHWDeviceContext {
     /**
      * A class for logging. Set by av_hwdevice_ctx_alloc().
      */
     const AVClass *av_class;
 
     /**
      * This field identifies the underlying API used for hardware access.
      *
      * This field is set when this struct is allocated and never changed
      * afterwards.
      */
     enum AVHWDeviceType type;
 
     /**
      * The format-specific data, allocated and freed by libavutil along with
      * this context.
      *
      * Should be cast by the user to the format-specific context defined in the
      * corresponding header (hwcontext_*.h) and filled as described in the
      * documentation before calling av_hwdevice_ctx_init().
      *
      * After calling av_hwdevice_ctx_init() this struct should not be modified
      * by the caller.
      */
     void *hwctx;
 
     /**
      * This field may be set by the caller before calling av_hwdevice_ctx_init().
      *
      * If non-NULL, this callback will be called when the last reference to
      * this context is unreferenced, immediately before it is freed.
      *
      * @note when other objects (e.g an AVHWFramesContext) are derived from this
      *       struct, this callback will be invoked after all such child objects
      *       are fully uninitialized and their respective destructors invoked.
      */
     void (*free)(struct AVHWDeviceContext *ctx);
 
     /**
      * Arbitrary user data, to be used e.g. by the free() callback.
      */
     void *user_opaque;
 } AVHWDeviceContext;
 
 /**
  * This struct describes a set or pool of "hardware" frames (i.e. those with
  * data not located in normal system memory). All the frames in the pool are
  * assumed to be allocated in the same way and interchangeable.
  *
  * This struct is reference-counted with the AVBuffer mechanism and tied to a
  * given AVHWDeviceContext instance. The av_hwframe_ctx_alloc() constructor
  * yields a reference, whose data field points to the actual AVHWFramesContext
  * struct.
  */
 typedef struct AVHWFramesContext {
     /**
      * A class for logging.
      */
     const AVClass *av_class;
 
     /**
      * A reference to the parent AVHWDeviceContext. This reference is owned and
      * managed by the enclosing AVHWFramesContext, but the caller may derive
      * additional references from it.
      */
     AVBufferRef *device_ref;
 
     /**
      * The parent AVHWDeviceContext. This is simply a pointer to
      * device_ref->data provided for convenience.
      *
      * Set by libavutil in av_hwframe_ctx_init().
      */
     AVHWDeviceContext *device_ctx;
 
     /**
      * The format-specific data, allocated and freed automatically along with
      * this context.
      *
      * The user shall ignore this field if the corresponding format-specific
      * header (hwcontext_*.h) does not define a context to be used as
      * AVHWFramesContext.hwctx.
      *
      * Otherwise, it should be cast by the user to said context and filled
      * as described in the documentation before calling av_hwframe_ctx_init().
      *
      * After any frames using this context are created, the contents of this
      * struct should not be modified by the caller.
      */
     void *hwctx;
 
     /**
      * This field may be set by the caller before calling av_hwframe_ctx_init().
      *
      * If non-NULL, this callback will be called when the last reference to
      * this context is unreferenced, immediately before it is freed.
      */
     void (*free)(struct AVHWFramesContext *ctx);
 
     /**
      * Arbitrary user data, to be used e.g. by the free() callback.
      */
     void *user_opaque;
 
     /**
      * A pool from which the frames are allocated by av_hwframe_get_buffer().
      * This field may be set by the caller before calling av_hwframe_ctx_init().
      * The buffers returned by calling av_buffer_pool_get() on this pool must
      * have the properties described in the documentation in the corresponding hw
      * type's header (hwcontext_*.h). The pool will be freed strictly before
      * this struct's free() callback is invoked.
      *
      * This field may be NULL, then libavutil will attempt to allocate a pool
      * internally. Note that certain device types enforce pools allocated at
      * fixed size (frame count), which cannot be extended dynamically. In such a
      * case, initial_pool_size must be set appropriately.
      */
     AVBufferPool *pool;
 
     /**
      * Initial size of the frame pool. If a device type does not support
      * dynamically resizing the pool, then this is also the maximum pool size.
      *
      * May be set by the caller before calling av_hwframe_ctx_init(). Must be
      * set if pool is NULL and the device type does not support dynamic pools.
      */
     int initial_pool_size;
 
     /**
      * The pixel format identifying the underlying HW surface type.
      *
      * Must be a hwaccel format, i.e. the corresponding descriptor must have the
      * AV_PIX_FMT_FLAG_HWACCEL flag set.
      *
      * Must be set by the user before calling av_hwframe_ctx_init().
      */
     enum AVPixelFormat format;
 
     /**
      * The pixel format identifying the actual data layout of the hardware
      * frames.
      *
      * Must be set by the caller before calling av_hwframe_ctx_init().
      *
      * @note when the underlying API does not provide the exact data layout, but
      * only the colorspace/bit depth, this field should be set to the fully
      * planar version of that format (e.g. for 8-bit 420 YUV it should be
      * AV_PIX_FMT_YUV420P, not AV_PIX_FMT_NV12 or anything else).
      */
     enum AVPixelFormat sw_format;
 
     /**
      * The allocated dimensions of the frames in this pool.
      *
      * Must be set by the user before calling av_hwframe_ctx_init().
      */
     int width, height;
 } AVHWFramesContext;
 
 /**
  * Look up an AVHWDeviceType by name.
  *
  * @param name String name of the device type (case-insensitive).
  * @return The type from enum AVHWDeviceType, or AV_HWDEVICE_TYPE_NONE if
  *         not found.
  */
 enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name);
 
 /** Get the string name of an AVHWDeviceType.
  *
  * @param type Type from enum AVHWDeviceType.
  * @return Pointer to a static string containing the name, or NULL if the type
  *         is not valid.
  */
 const char *av_hwdevice_get_type_name(enum AVHWDeviceType type);
 
 /**
  * Iterate over supported device types.
  *
  * @param prev AV_HWDEVICE_TYPE_NONE initially, then the previous type
  *             returned by this function in subsequent iterations.
  * @return The next usable device type from enum AVHWDeviceType, or
  *         AV_HWDEVICE_TYPE_NONE if there are no more.
  */
 enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev);
 
 /**
  * Allocate an AVHWDeviceContext for a given hardware type.
  *
  * @param type the type of the hardware device to allocate.
  * @return a reference to the newly created AVHWDeviceContext on success or NULL
  *         on failure.
  */
 AVBufferRef *av_hwdevice_ctx_alloc(enum AVHWDeviceType type);
 
 /**
  * Finalize the device context before use. This function must be called after
  * the context is filled with all the required information and before it is
  * used in any way.
  *
  * @param ref a reference to the AVHWDeviceContext
  * @return 0 on success, a negative AVERROR code on failure
  */
 int av_hwdevice_ctx_init(AVBufferRef *ref);
 
 /**
  * Open a device of the specified type and create an AVHWDeviceContext for it.
  *
  * This is a convenience function intended to cover the simple cases. Callers
  * who need to fine-tune device creation/management should open the device
  * manually and then wrap it in an AVHWDeviceContext using
  * av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
  *
  * The returned context is already initialized and ready for use, the caller
  * should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
  * the created AVHWDeviceContext are set by this function and should not be
  * touched by the caller.
  *
  * @param device_ctx On success, a reference to the newly-created device context
  *                   will be written here. The reference is owned by the caller
  *                   and must be released with av_buffer_unref() when no longer
  *                   needed. On failure, NULL will be written to this pointer.
  * @param type The type of the device to create.
  * @param device A type-specific string identifying the device to open.
  * @param opts A dictionary of additional (type-specific) options to use in
  *             opening the device. The dictionary remains owned by the caller.
  * @param flags currently unused
  *
  * @return 0 on success, a negative AVERROR code on failure.
  */
 int av_hwdevice_ctx_create(AVBufferRef **device_ctx, enum AVHWDeviceType type,
                            const char *device, AVDictionary *opts, int flags);
 
 /**
  * Create a new device of the specified type from an existing device.
  *
  * If the source device is a device of the target type or was originally
  * derived from such a device (possibly through one or more intermediate
  * devices of other types), then this will return a reference to the
  * existing device of the same type as is requested.
  *
  * Otherwise, it will attempt to derive a new device from the given source
  * device.  If direct derivation to the new type is not implemented, it will
  * attempt the same derivation from each ancestor of the source device in
  * turn looking for an implemented derivation method.
  *
  * @param dst_ctx On success, a reference to the newly-created
  *                AVHWDeviceContext.
  * @param type    The type of the new device to create.
  * @param src_ctx A reference to an existing AVHWDeviceContext which will be
  *                used to create the new device.
  * @param flags   Currently unused; should be set to zero.
  * @return        Zero on success, a negative AVERROR code on failure.
  */
 int av_hwdevice_ctx_create_derived(AVBufferRef **dst_ctx,
                                    enum AVHWDeviceType type,
                                    AVBufferRef *src_ctx, int flags);
 
 /**
  * Create a new device of the specified type from an existing device.
  *
  * This function performs the same action as av_hwdevice_ctx_create_derived,
  * however, it is able to set options for the new device to be derived.
  *
  * @param dst_ctx On success, a reference to the newly-created
  *                AVHWDeviceContext.
  * @param type    The type of the new device to create.
  * @param src_ctx A reference to an existing AVHWDeviceContext which will be
  *                used to create the new device.
  * @param options Options for the new device to create, same format as in
  *                av_hwdevice_ctx_create.
  * @param flags   Currently unused; should be set to zero.
  * @return        Zero on success, a negative AVERROR code on failure.
  */
 int av_hwdevice_ctx_create_derived_opts(AVBufferRef **dst_ctx,
                                         enum AVHWDeviceType type,
                                         AVBufferRef *src_ctx,
                                         AVDictionary *options, int flags);
 
 /**
  * Allocate an AVHWFramesContext tied to a given device context.
  *
  * @param device_ctx a reference to a AVHWDeviceContext. This function will make
  *                   a new reference for internal use, the one passed to the
  *                   function remains owned by the caller.
  * @return a reference to the newly created AVHWFramesContext on success or NULL
  *         on failure.
  */
 AVBufferRef *av_hwframe_ctx_alloc(AVBufferRef *device_ctx);
 
 /**
  * Finalize the context before use. This function must be called after the
  * context is filled with all the required information and before it is attached
  * to any frames.
  *
  * @param ref a reference to the AVHWFramesContext
  * @return 0 on success, a negative AVERROR code on failure
  */
 int av_hwframe_ctx_init(AVBufferRef *ref);
 
 /**
  * Allocate a new frame attached to the given AVHWFramesContext.
  *
  * @param hwframe_ctx a reference to an AVHWFramesContext
  * @param frame an empty (freshly allocated or unreffed) frame to be filled with
  *              newly allocated buffers.
  * @param flags currently unused, should be set to zero
  * @return 0 on success, a negative AVERROR code on failure
  */
 int av_hwframe_get_buffer(AVBufferRef *hwframe_ctx, AVFrame *frame, int flags);
 
 /**
  * Copy data to or from a hw surface. At least one of dst/src must have an
  * AVHWFramesContext attached.
  *
  * If src has an AVHWFramesContext attached, then the format of dst (if set)
  * must use one of the formats returned by av_hwframe_transfer_get_formats(src,
  * AV_HWFRAME_TRANSFER_DIRECTION_FROM).
  * If dst has an AVHWFramesContext attached, then the format of src must use one
  * of the formats returned by av_hwframe_transfer_get_formats(dst,
  * AV_HWFRAME_TRANSFER_DIRECTION_TO)
  *
  * dst may be "clean" (i.e. with data/buf pointers unset), in which case the
  * data buffers will be allocated by this function using av_frame_get_buffer().
  * If dst->format is set, then this format will be used, otherwise (when
  * dst->format is AV_PIX_FMT_NONE) the first acceptable format will be chosen.
  *
  * The two frames must have matching allocated dimensions (i.e. equal to
  * AVHWFramesContext.width/height), since not all device types support
  * transferring a sub-rectangle of the whole surface. The display dimensions
  * (i.e. AVFrame.width/height) may be smaller than the allocated dimensions, but
  * also have to be equal for both frames. When the display dimensions are
  * smaller than the allocated dimensions, the content of the padding in the
  * destination frame is unspecified.
  *
  * @param dst the destination frame. dst is not touched on failure.
  * @param src the source frame.
  * @param flags currently unused, should be set to zero
  * @return 0 on success, a negative AVERROR error code on failure.
  */
 int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags);
 
 enum AVHWFrameTransferDirection {
     /**
      * Transfer the data from the queried hw frame.
      */
     AV_HWFRAME_TRANSFER_DIRECTION_FROM,
 
     /**
      * Transfer the data to the queried hw frame.
      */
     AV_HWFRAME_TRANSFER_DIRECTION_TO,
 };
 
 /**
  * Get a list of possible source or target formats usable in
  * av_hwframe_transfer_data().
  *
  * @param hwframe_ctx the frame context to obtain the information for
  * @param dir the direction of the transfer
  * @param formats the pointer to the output format list will be written here.
  *                The list is terminated with AV_PIX_FMT_NONE and must be freed
  *                by the caller when no longer needed using av_free().
  *                If this function returns successfully, the format list will
  *                have at least one item (not counting the terminator).
  *                On failure, the contents of this pointer are unspecified.
  * @param flags currently unused, should be set to zero
  * @return 0 on success, a negative AVERROR code on failure.
  */
 int av_hwframe_transfer_get_formats(AVBufferRef *hwframe_ctx,
                                     enum AVHWFrameTransferDirection dir,
                                     enum AVPixelFormat **formats, int flags);
 
 
 /**
  * This struct describes the constraints on hardware frames attached to
  * a given device with a hardware-specific configuration.  This is returned
  * by av_hwdevice_get_hwframe_constraints() and must be freed by
  * av_hwframe_constraints_free() after use.
  */
 typedef struct AVHWFramesConstraints {
     /**
      * A list of possible values for format in the hw_frames_ctx,
      * terminated by AV_PIX_FMT_NONE.  This member will always be filled.
      */
     enum AVPixelFormat *valid_hw_formats;
 
     /**
      * A list of possible values for sw_format in the hw_frames_ctx,
      * terminated by AV_PIX_FMT_NONE.  Can be NULL if this information is
      * not known.
      */
     enum AVPixelFormat *valid_sw_formats;
 
     /**
      * The minimum size of frames in this hw_frames_ctx.
      * (Zero if not known.)
      */
     int min_width;
     int min_height;
 
     /**
      * The maximum size of frames in this hw_frames_ctx.
      * (INT_MAX if not known / no limit.)
      */
     int max_width;
     int max_height;
 } AVHWFramesConstraints;
 
 /**
  * Allocate a HW-specific configuration structure for a given HW device.
  * After use, the user must free all members as required by the specific
  * hardware structure being used, then free the structure itself with
  * av_free().
  *
  * @param device_ctx a reference to the associated AVHWDeviceContext.
  * @return The newly created HW-specific configuration structure on
  *         success or NULL on failure.
  */
 void *av_hwdevice_hwconfig_alloc(AVBufferRef *device_ctx);
 
 /**
  * Get the constraints on HW frames given a device and the HW-specific
  * configuration to be used with that device.  If no HW-specific
  * configuration is provided, returns the maximum possible capabilities
  * of the device.
  *
  * @param ref a reference to the associated AVHWDeviceContext.
  * @param hwconfig a filled HW-specific configuration structure, or NULL
  *        to return the maximum possible capabilities of the device.
  * @return AVHWFramesConstraints structure describing the constraints
  *         on the device, or NULL if not available.
  */
 AVHWFramesConstraints *av_hwdevice_get_hwframe_constraints(AVBufferRef *ref,
                                                            const void *hwconfig);
 
 /**
  * Free an AVHWFrameConstraints structure.
  *
  * @param constraints The (filled or unfilled) AVHWFrameConstraints structure.
  */
 void av_hwframe_constraints_free(AVHWFramesConstraints **constraints);
 
 
 /**
  * Flags to apply to frame mappings.
  */
 enum {
     /**
      * The mapping must be readable.
      */
     AV_HWFRAME_MAP_READ      = 1 << 0,
     /**
      * The mapping must be writeable.
      */
     AV_HWFRAME_MAP_WRITE     = 1 << 1,
     /**
      * The mapped frame will be overwritten completely in subsequent
      * operations, so the current frame data need not be loaded.  Any values
      * which are not overwritten are unspecified.
      */
     AV_HWFRAME_MAP_OVERWRITE = 1 << 2,
     /**
      * The mapping must be direct.  That is, there must not be any copying in
      * the map or unmap steps.  Note that performance of direct mappings may
      * be much lower than normal memory.
      */
     AV_HWFRAME_MAP_DIRECT    = 1 << 3,
 };
 
 /**
  * Map a hardware frame.
  *
  * This has a number of different possible effects, depending on the format
  * and origin of the src and dst frames.  On input, src should be a usable
  * frame with valid buffers and dst should be blank (typically as just created
  * by av_frame_alloc()).  src should have an associated hwframe context, and
  * dst may optionally have a format and associated hwframe context.
  *
  * If src was created by mapping a frame from the hwframe context of dst,
  * then this function undoes the mapping - dst is replaced by a reference to
  * the frame that src was originally mapped from.
  *
  * If both src and dst have an associated hwframe context, then this function
  * attempts to map the src frame from its hardware context to that of dst and
  * then fill dst with appropriate data to be usable there.  This will only be
  * possible if the hwframe contexts and associated devices are compatible -
  * given compatible devices, av_hwframe_ctx_create_derived() can be used to
  * create a hwframe context for dst in which mapping should be possible.
  *
  * If src has a hwframe context but dst does not, then the src frame is
  * mapped to normal memory and should thereafter be usable as a normal frame.
  * If the format is set on dst, then the mapping will attempt to create dst
  * with that format and fail if it is not possible.  If format is unset (is
  * AV_PIX_FMT_NONE) then dst will be mapped with whatever the most appropriate
  * format to use is (probably the sw_format of the src hwframe context).
  *
  * A return value of AVERROR(ENOSYS) indicates that the mapping is not
  * possible with the given arguments and hwframe setup, while other return
  * values indicate that it failed somehow.
  *
  * On failure, the destination frame will be left blank, except for the
  * hw_frames_ctx/format fields thay may have been set by the caller - those will
  * be preserved as they were.
  *
  * @param dst Destination frame, to contain the mapping.
  * @param src Source frame, to be mapped.
  * @param flags Some combination of AV_HWFRAME_MAP_* flags.
  * @return Zero on success, negative AVERROR code on failure.
  */
 int av_hwframe_map(AVFrame *dst, const AVFrame *src, int flags);
 
 
 /**
  * Create and initialise an AVHWFramesContext as a mapping of another existing
  * AVHWFramesContext on a different device.
  *
  * av_hwframe_ctx_init() should not be called after this.
  *
  * @param derived_frame_ctx  On success, a reference to the newly created
  *                           AVHWFramesContext.
  * @param format             The AVPixelFormat for the derived context.
  * @param derived_device_ctx A reference to the device to create the new
  *                           AVHWFramesContext on.
  * @param source_frame_ctx   A reference to an existing AVHWFramesContext
  *                           which will be mapped to the derived context.
  * @param flags  Some combination of AV_HWFRAME_MAP_* flags, defining the
  *               mapping parameters to apply to frames which are allocated
  *               in the derived device.
  * @return       Zero on success, negative AVERROR code on failure.
  */
 int av_hwframe_ctx_create_derived(AVBufferRef **derived_frame_ctx,
                                   enum AVPixelFormat format,
                                   AVBufferRef *derived_device_ctx,
                                   AVBufferRef *source_frame_ctx,
                                   int flags);
 
 #endif /* AVUTIL_HWCONTEXT_H */