chromium/third_party/libaom/source/libaom/aom/aom_encoder.h

/*
 * Copyright (c) 2016, Alliance for Open Media. All rights reserved.
 *
 * This source code is subject to the terms of the BSD 2 Clause License and
 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
 * was not distributed with this source code in the LICENSE file, you can
 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
 * Media Patent License 1.0 was not distributed with this source code in the
 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
 */
#ifndef AOM_AOM_AOM_ENCODER_H_
#define AOM_AOM_AOM_ENCODER_H_

/*!\defgroup encoder Encoder Algorithm Interface
 * \ingroup codec
 * This abstraction allows applications using this encoder to easily support
 * multiple video formats with minimal code duplication. This section describes
 * the interface common to all encoders.
 * @{
 */

/*!\file
 * \brief Describes the encoder algorithm interface to applications.
 *
 * This file describes the interface between an application and a
 * video encoder algorithm.
 *
 */
#ifdef __cplusplus
extern "C" {
#endif

#include "aom/aom_codec.h"  // IWYU pragma: export
#include "aom/aom_external_partition.h"

/*!\brief Current ABI version number
 *
 * \hideinitializer
 * \internal
 * If this file is altered in any way that changes the ABI, this value
 * must be bumped.  Examples include, but are not limited to, changing
 * types, removing or reassigning enums, adding/removing/rearranging
 * fields to structures
 *
 * Note: In the definition of AOM_ENCODER_ABI_VERSION, 3 is the value of
 * AOM_EXT_PART_ABI_VERSION in libaom v3.2.0. The old value of
 * AOM_EXT_PART_ABI_VERSION is used so as to not break the ABI version check in
 * aom_codec_enc_init_ver() when an application compiled against libaom v3.2.0
 * passes the old value of AOM_ENCODER_ABI_VERSION to aom_codec_enc_init_ver().
 * The external partition API is still experimental. When it is declared stable,
 * we will replace 3 with AOM_EXT_PART_ABI_VERSION in the definition of
 * AOM_ENCODER_ABI_VERSION.
 */
#define AOM_ENCODER_ABI_VERSION

/*! \brief Encoder capabilities bitfield
 *
 *  Each encoder advertises the capabilities it supports as part of its
 *  ::aom_codec_iface_t interface structure. Capabilities are extra
 *  interfaces or functionality, and are not required to be supported
 *  by an encoder.
 *
 *  The available flags are specified by AOM_CODEC_CAP_* defines.
 */
#define AOM_CODEC_CAP_PSNR

/*! Can support input images at greater than 8 bitdepth.
 */
#define AOM_CODEC_CAP_HIGHBITDEPTH

/*! \brief Initialization-time Feature Enabling
 *
 *  Certain codec features must be known at initialization time, to allow
 *  for proper memory allocation.
 *
 *  The available flags are specified by AOM_CODEC_USE_* defines.
 */
#define AOM_CODEC_USE_PSNR
#define AOM_CODEC_USE_HIGHBITDEPTH

/*!\brief Generic fixed size buffer structure
 *
 * This structure is able to hold a reference to any fixed size buffer.
 */
aom_fixed_buf_t; /**< alias for struct aom_fixed_buf */

/*!\brief Error Resilient flags
 *
 * These flags define which error resilient features to enable in the
 * encoder. The flags are specified through the
 * aom_codec_enc_cfg::g_error_resilient variable.
 */
aom_codec_er_flags_t;
/*!\brief Improve resiliency against losses of whole frames */
#define AOM_ERROR_RESILIENT_DEFAULT

/*!\brief Encoder output packet variants
 *
 * This enumeration lists the different kinds of data packets that can be
 * returned by calls to aom_codec_get_cx_data(). Algorithms \ref MAY
 * extend this list to provide additional functionality.
 */
enum aom_codec_cx_pkt_kind {};

/*!\brief Encoder output packet
 *
 * This structure contains the different kinds of output data the encoder
 * may produce while compressing a frame.
 */
aom_codec_cx_pkt_t;    /**< alias for struct aom_codec_cx_pkt */

/*!\brief Rational Number
 *
 * This structure holds a fractional value.
 */
aom_rational_t; /**< alias for struct aom_rational */

/*!\brief Multi-pass Encoding Pass
 *
 * AOM_RC_LAST_PASS is kept for backward compatibility.
 * If passes is not given and pass==2, the codec will assume passes=2.
 * For new code, it is recommended to use AOM_RC_SECOND_PASS and set
 * the "passes" member to 2 via the key & val API for two-pass encoding.
 */
enum aom_enc_pass {};

/*!\brief Rate control mode */
enum aom_rc_mode {};

/*!\brief Keyframe placement mode.
 *
 * This enumeration determines whether keyframes are placed automatically by
 * the encoder or whether this behavior is disabled. Older releases of this
 * SDK were implemented such that AOM_KF_FIXED meant keyframes were disabled.
 * This name is confusing for this behavior, so the new symbols to be used
 * are AOM_KF_AUTO and AOM_KF_DISABLED.
 */
enum aom_kf_mode {};

/*!\brief Frame super-resolution mode. */
aom_superres_mode;

/*!\brief Encoder Config Options
 *
 * This type allows to enumerate and control flags defined for encoder control
 * via config file at runtime.
 */
cfg_options_t;

/*!\brief Encoded Frame Flags
 *
 * This type indicates a bitfield to be passed to aom_codec_encode(), defining
 * per-frame boolean values. By convention, bits common to all codecs will be
 * named AOM_EFLAG_*, and bits specific to an algorithm will be named
 * /algo/_eflag_*. The lower order 16 bits are reserved for common use.
 */
aom_enc_frame_flags_t;
/*!\brief Force this frame to be a keyframe */
#define AOM_EFLAG_FORCE_KF

/*!\brief Encoder configuration structure
 *
 * This structure contains the encoder settings that have common representations
 * across all codecs. This doesn't imply that all codecs support all features,
 * however.
 */
aom_codec_enc_cfg_t; /**< alias for struct aom_codec_enc_cfg */

/*!\brief Initialize an encoder instance
 *
 * Initializes an encoder context using the given interface. Applications
 * should call the aom_codec_enc_init convenience macro instead of this
 * function directly, to ensure that the ABI version number parameter
 * is properly initialized.
 *
 * If the library was configured with -DCONFIG_MULTITHREAD=0, this call
 * is not thread safe and should be guarded with a lock if being used
 * in a multithreaded context.
 *
 * If aom_codec_enc_init_ver() fails, it is not necessary to call
 * aom_codec_destroy() on the encoder context.
 *
 * \param[in]    ctx     Pointer to this instance's context.
 * \param[in]    iface   Pointer to the algorithm interface to use.
 * \param[in]    cfg     Configuration to use, if known.
 * \param[in]    flags   Bitfield of AOM_CODEC_USE_* flags
 * \param[in]    ver     ABI version number. Must be set to
 *                       AOM_ENCODER_ABI_VERSION
 * \retval #AOM_CODEC_OK
 *     The encoder algorithm has been initialized.
 * \retval #AOM_CODEC_MEM_ERROR
 *     Memory allocation failed.
 */
aom_codec_err_t aom_codec_enc_init_ver(aom_codec_ctx_t *ctx,
                                       aom_codec_iface_t *iface,
                                       const aom_codec_enc_cfg_t *cfg,
                                       aom_codec_flags_t flags, int ver);

/*!\brief Convenience macro for aom_codec_enc_init_ver()
 *
 * Ensures the ABI version parameter is properly set.
 */
#define aom_codec_enc_init(ctx, iface, cfg, flags)

/*!\brief Get the default configuration for a usage.
 *
 * Initializes an encoder configuration structure with default values. Supports
 * the notion of "usages" so that an algorithm may offer different default
 * settings depending on the user's intended goal. This function \ref SHOULD
 * be called by all applications to initialize the configuration structure
 * before specializing the configuration with application specific values.
 *
 * \param[in]    iface     Pointer to the algorithm interface to use.
 * \param[out]   cfg       Configuration buffer to populate.
 * \param[in]    usage     Algorithm specific usage value. For AV1, must be
 *                         set to AOM_USAGE_GOOD_QUALITY (0),
 *                         AOM_USAGE_REALTIME (1), or AOM_USAGE_ALL_INTRA (2).
 *
 * \retval #AOM_CODEC_OK
 *     The configuration was populated.
 * \retval #AOM_CODEC_INCAPABLE
 *     Interface is not an encoder interface.
 * \retval #AOM_CODEC_INVALID_PARAM
 *     A parameter was NULL, or the usage value was not recognized.
 */
aom_codec_err_t aom_codec_enc_config_default(aom_codec_iface_t *iface,
                                             aom_codec_enc_cfg_t *cfg,
                                             unsigned int usage);

/*!\brief Set or change configuration
 *
 * Reconfigures an encoder instance according to the given configuration.
 *
 * \param[in]    ctx     Pointer to this instance's context
 * \param[in]    cfg     Configuration buffer to use
 *
 * \retval #AOM_CODEC_OK
 *     The configuration was populated.
 * \retval #AOM_CODEC_INCAPABLE
 *     Interface is not an encoder interface.
 * \retval #AOM_CODEC_INVALID_PARAM
 *     A parameter was NULL, or the usage value was not recognized.
 */
aom_codec_err_t aom_codec_enc_config_set(aom_codec_ctx_t *ctx,
                                         const aom_codec_enc_cfg_t *cfg);

/*!\brief Get global stream headers
 *
 * Retrieves a stream level global header packet, if supported by the codec.
 * Calls to this function should be deferred until all configuration information
 * has been passed to libaom. Otherwise the global header data may be
 * invalidated by additional configuration changes.
 *
 * The AV1 implementation of this function returns an OBU. The OBU returned is
 * in Low Overhead Bitstream Format. Specifically, the obu_has_size_field bit is
 * set, and the buffer contains the obu_size field for the returned OBU.
 *
 * \param[in]    ctx     Pointer to this instance's context
 *
 * \retval NULL
 *     Encoder does not support global header, or an error occurred while
 *     generating the global header.
 *
 * \retval Non-NULL
 *     Pointer to buffer containing global header packet. The caller owns the
 *     memory associated with this buffer, and must free the 'buf' member of the
 *     aom_fixed_buf_t as well as the aom_fixed_buf_t pointer. Memory returned
 *     must be freed via call to free().
 */
aom_fixed_buf_t *aom_codec_get_global_headers(aom_codec_ctx_t *ctx);

/*!\brief usage parameter analogous to AV1 GOOD QUALITY mode. */
#define AOM_USAGE_GOOD_QUALITY
/*!\brief usage parameter analogous to AV1 REALTIME mode. */
#define AOM_USAGE_REALTIME
/*!\brief usage parameter analogous to AV1 all intra mode. */
#define AOM_USAGE_ALL_INTRA

/*!\brief Encode a frame
 *
 * Encodes a video frame at the given "presentation time." The presentation
 * time stamp (PTS) \ref MUST be strictly increasing.
 *
 * When the last frame has been passed to the encoder, this function should
 * continue to be called in a loop, with the img parameter set to NULL. This
 * will signal the end-of-stream condition to the encoder and allow it to
 * encode any held buffers. Encoding is complete when aom_codec_encode() is
 * called with img set to NULL and aom_codec_get_cx_data() returns no data.
 *
 * \param[in]    ctx       Pointer to this instance's context
 * \param[in]    img       Image data to encode, NULL to flush.
 *                         Encoding sample values outside the range
 *                         [0..(1<<img->bit_depth)-1] is undefined behavior.
 *                         Note: Although img is declared as a const pointer,
 *                         if AV1E_SET_DENOISE_NOISE_LEVEL is set to a nonzero
 *                         value aom_codec_encode() modifies (denoises) the
 *                         samples in img->planes[i] .
 * \param[in]    pts       Presentation time stamp, in timebase units. If img
 *                         is NULL, pts is ignored.
 * \param[in]    duration  Duration to show frame, in timebase units. If img
 *                         is not NULL, duration must be nonzero. If img is
 *                         NULL, duration is ignored.
 * \param[in]    flags     Flags to use for encoding this frame.
 *
 * \retval #AOM_CODEC_OK
 *     The configuration was populated.
 * \retval #AOM_CODEC_INCAPABLE
 *     Interface is not an encoder interface.
 * \retval #AOM_CODEC_INVALID_PARAM
 *     A parameter was NULL, the image format is unsupported, etc.
 *
 * \note
 * `duration` is of the unsigned long type, which can be 32 or 64 bits.
 * `duration` must be less than or equal to UINT32_MAX so that its range is
 * independent of the size of unsigned long.
 */
aom_codec_err_t aom_codec_encode(aom_codec_ctx_t *ctx, const aom_image_t *img,
                                 aom_codec_pts_t pts, unsigned long duration,
                                 aom_enc_frame_flags_t flags);

/*!\brief Set compressed data output buffer
 *
 * Sets the buffer that the codec should output the compressed data
 * into. This call effectively sets the buffer pointer returned in the
 * next AOM_CODEC_CX_FRAME_PKT packet. Subsequent packets will be
 * appended into this buffer. The buffer is preserved across frames,
 * so applications must periodically call this function after flushing
 * the accumulated compressed data to disk or to the network to reset
 * the pointer to the buffer's head.
 *
 * `pad_before` bytes will be skipped before writing the compressed
 * data, and `pad_after` bytes will be appended to the packet. The size
 * of the packet will be the sum of the size of the actual compressed
 * data, pad_before, and pad_after. The padding bytes will be preserved
 * (not overwritten).
 *
 * Note that calling this function does not guarantee that the returned
 * compressed data will be placed into the specified buffer. In the
 * event that the encoded data will not fit into the buffer provided,
 * the returned packet \ref MAY point to an internal buffer, as it would
 * if this call were never used. In this event, the output packet will
 * NOT have any padding, and the application must free space and copy it
 * to the proper place. This is of particular note in configurations
 * that may output multiple packets for a single encoded frame (e.g., lagged
 * encoding) or if the application does not reset the buffer periodically.
 *
 * Applications may restore the default behavior of the codec providing
 * the compressed data buffer by calling this function with a NULL
 * buffer.
 *
 * Applications \ref MUSTNOT call this function during iteration of
 * aom_codec_get_cx_data().
 *
 * \param[in]    ctx         Pointer to this instance's context
 * \param[in]    buf         Buffer to store compressed data into
 * \param[in]    pad_before  Bytes to skip before writing compressed data
 * \param[in]    pad_after   Bytes to skip after writing compressed data
 *
 * \retval #AOM_CODEC_OK
 *     The buffer was set successfully.
 * \retval #AOM_CODEC_INVALID_PARAM
 *     A parameter was NULL, the image format is unsupported, etc.
 */
aom_codec_err_t aom_codec_set_cx_data_buf(aom_codec_ctx_t *ctx,
                                          const aom_fixed_buf_t *buf,
                                          unsigned int pad_before,
                                          unsigned int pad_after);

/*!\brief Encoded data iterator
 *
 * Iterates over a list of data packets to be passed from the encoder to the
 * application. The different kinds of packets available are enumerated in
 * #aom_codec_cx_pkt_kind.
 *
 * #AOM_CODEC_CX_FRAME_PKT packets should be passed to the application's
 * muxer. Multiple compressed frames may be in the list.
 * #AOM_CODEC_STATS_PKT packets should be appended to a global buffer.
 *
 * The application \ref MUST silently ignore any packet kinds that it does
 * not recognize or support.
 *
 * The data buffers returned from this function are only guaranteed to be
 * valid until the application makes another call to any aom_codec_* function.
 *
 * \param[in]     ctx      Pointer to this instance's context
 * \param[in,out] iter     Iterator storage, initialized to NULL
 *
 * \return Returns a pointer to an output data packet (compressed frame data,
 *         two-pass statistics, etc.) or NULL to signal end-of-list.
 *
 */
const aom_codec_cx_pkt_t *aom_codec_get_cx_data(aom_codec_ctx_t *ctx,
                                                aom_codec_iter_t *iter);

/*!\brief Get Preview Frame
 *
 * Returns an image that can be used as a preview. Shows the image as it would
 * exist at the decompressor. The application \ref MUST NOT write into this
 * image buffer.
 *
 * \param[in]     ctx      Pointer to this instance's context
 *
 * \return Returns a pointer to a preview image, or NULL if no image is
 *         available.
 *
 */
const aom_image_t *aom_codec_get_preview_frame(aom_codec_ctx_t *ctx);

/*!@} - end defgroup encoder*/
#ifdef __cplusplus
}
#endif
#endif  // AOM_AOM_AOM_ENCODER_H_