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      1 /*
      2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
      3  *
      4  *  Use of this source code is governed by a BSD-style license
      5  *  that can be found in the LICENSE file in the root of the source
      6  *  tree. An additional intellectual property rights grant can be found
      7  *  in the file PATENTS.  All contributing project authors may
      8  *  be found in the AUTHORS file in the root of the source tree.
      9  */
     10 #ifndef VPX_VPX_ENCODER_H_
     11 #define VPX_VPX_ENCODER_H_
     12 
     13 /*!\defgroup encoder Encoder Algorithm Interface
     14  * \ingroup codec
     15  * This abstraction allows applications using this encoder to easily support
     16  * multiple video formats with minimal code duplication. This section describes
     17  * the interface common to all encoders.
     18  * @{
     19  */
     20 
     21 /*!\file
     22  * \brief Describes the encoder algorithm interface to applications.
     23  *
     24  * This file describes the interface between an application and a
     25  * video encoder algorithm.
     26  *
     27  */
     28 #ifdef __cplusplus
     29 extern "C" {
     30 #endif
     31 
     32 #include "./vpx_codec.h"
     33 
     34 /*! Temporal Scalability: Maximum length of the sequence defining frame
     35  * layer membership
     36  */
     37 #define VPX_TS_MAX_PERIODICITY 16
     38 
     39 /*! Temporal Scalability: Maximum number of coding layers */
     40 #define VPX_TS_MAX_LAYERS 5
     41 
     42 /*!\deprecated Use #VPX_TS_MAX_PERIODICITY instead. */
     43 #define MAX_PERIODICITY VPX_TS_MAX_PERIODICITY
     44 
     45 /*! Temporal+Spatial Scalability: Maximum number of coding layers */
     46 #define VPX_MAX_LAYERS 12  // 3 temporal + 4 spatial layers are allowed.
     47 
     48 /*!\deprecated Use #VPX_MAX_LAYERS instead. */
     49 #define MAX_LAYERS VPX_MAX_LAYERS  // 3 temporal + 4 spatial layers allowed.
     50 
     51 /*! Spatial Scalability: Maximum number of coding layers */
     52 #define VPX_SS_MAX_LAYERS 5
     53 
     54 /*! Spatial Scalability: Default number of coding layers */
     55 #define VPX_SS_DEFAULT_LAYERS 1
     56 
     57 /*!\brief Current ABI version number
     58  *
     59  * \internal
     60  * If this file is altered in any way that changes the ABI, this value
     61  * must be bumped.  Examples include, but are not limited to, changing
     62  * types, removing or reassigning enums, adding/removing/rearranging
     63  * fields to structures
     64  */
     65 #define VPX_ENCODER_ABI_VERSION \
     66   (5 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/
     67 
     68 /*! \brief Encoder capabilities bitfield
     69  *
     70  *  Each encoder advertises the capabilities it supports as part of its
     71  *  ::vpx_codec_iface_t interface structure. Capabilities are extra
     72  *  interfaces or functionality, and are not required to be supported
     73  *  by an encoder.
     74  *
     75  *  The available flags are specified by VPX_CODEC_CAP_* defines.
     76  */
     77 #define VPX_CODEC_CAP_PSNR 0x10000 /**< Can issue PSNR packets */
     78 
     79 /*! Can output one partition at a time. Each partition is returned in its
     80  *  own VPX_CODEC_CX_FRAME_PKT, with the FRAME_IS_FRAGMENT flag set for
     81  *  every partition but the last. In this mode all frames are always
     82  *  returned partition by partition.
     83  */
     84 #define VPX_CODEC_CAP_OUTPUT_PARTITION 0x20000
     85 
     86 /*! \brief Initialization-time Feature Enabling
     87  *
     88  *  Certain codec features must be known at initialization time, to allow
     89  *  for proper memory allocation.
     90  *
     91  *  The available flags are specified by VPX_CODEC_USE_* defines.
     92  */
     93 #define VPX_CODEC_USE_PSNR 0x10000 /**< Calculate PSNR on each frame */
     94 /*!\brief Make the encoder output one  partition at a time. */
     95 #define VPX_CODEC_USE_OUTPUT_PARTITION 0x20000
     96 #define VPX_CODEC_USE_HIGHBITDEPTH 0x40000 /**< Use high bitdepth */
     97 
     98 /*!\brief Generic fixed size buffer structure
     99  *
    100  * This structure is able to hold a reference to any fixed size buffer.
    101  */
    102 typedef struct vpx_fixed_buf {
    103   void *buf;       /**< Pointer to the data */
    104   size_t sz;       /**< Length of the buffer, in chars */
    105 } vpx_fixed_buf_t; /**< alias for struct vpx_fixed_buf */
    106 
    107 /*!\brief Time Stamp Type
    108  *
    109  * An integer, which when multiplied by the stream's time base, provides
    110  * the absolute time of a sample.
    111  */
    112 typedef int64_t vpx_codec_pts_t;
    113 
    114 /*!\brief Compressed Frame Flags
    115  *
    116  * This type represents a bitfield containing information about a compressed
    117  * frame that may be useful to an application. The most significant 16 bits
    118  * can be used by an algorithm to provide additional detail, for example to
    119  * support frame types that are codec specific (MPEG-1 D-frames for example)
    120  */
    121 typedef uint32_t vpx_codec_frame_flags_t;
    122 #define VPX_FRAME_IS_KEY 0x1 /**< frame is the start of a GOP */
    123 /*!\brief frame can be dropped without affecting the stream (no future frame
    124  * depends on this one) */
    125 #define VPX_FRAME_IS_DROPPABLE 0x2
    126 /*!\brief frame should be decoded but will not be shown */
    127 #define VPX_FRAME_IS_INVISIBLE 0x4
    128 /*!\brief this is a fragment of the encoded frame */
    129 #define VPX_FRAME_IS_FRAGMENT 0x8
    130 
    131 /*!\brief Error Resilient flags
    132  *
    133  * These flags define which error resilient features to enable in the
    134  * encoder. The flags are specified through the
    135  * vpx_codec_enc_cfg::g_error_resilient variable.
    136  */
    137 typedef uint32_t vpx_codec_er_flags_t;
    138 /*!\brief Improve resiliency against losses of whole frames */
    139 #define VPX_ERROR_RESILIENT_DEFAULT 0x1
    140 /*!\brief The frame partitions are independently decodable by the bool decoder,
    141  * meaning that partitions can be decoded even though earlier partitions have
    142  * been lost. Note that intra prediction is still done over the partition
    143  * boundary. */
    144 #define VPX_ERROR_RESILIENT_PARTITIONS 0x2
    145 
    146 /*!\brief Encoder output packet variants
    147  *
    148  * This enumeration lists the different kinds of data packets that can be
    149  * returned by calls to vpx_codec_get_cx_data(). Algorithms \ref MAY
    150  * extend this list to provide additional functionality.
    151  */
    152 enum vpx_codec_cx_pkt_kind {
    153   VPX_CODEC_CX_FRAME_PKT,   /**< Compressed video frame */
    154   VPX_CODEC_STATS_PKT,      /**< Two-pass statistics for this frame */
    155   VPX_CODEC_FPMB_STATS_PKT, /**< first pass mb statistics for this frame */
    156   VPX_CODEC_PSNR_PKT,       /**< PSNR statistics for this frame */
    157 // Spatial SVC is still experimental and may be removed before the next ABI
    158 // bump.
    159 #if VPX_ENCODER_ABI_VERSION > (5 + VPX_CODEC_ABI_VERSION)
    160   VPX_CODEC_SPATIAL_SVC_LAYER_SIZES, /**< Sizes for each layer in this frame*/
    161   VPX_CODEC_SPATIAL_SVC_LAYER_PSNR,  /**< PSNR for each layer in this frame*/
    162 #endif
    163   VPX_CODEC_CUSTOM_PKT = 256 /**< Algorithm extensions  */
    164 };
    165 
    166 /*!\brief Encoder output packet
    167  *
    168  * This structure contains the different kinds of output data the encoder
    169  * may produce while compressing a frame.
    170  */
    171 typedef struct vpx_codec_cx_pkt {
    172   enum vpx_codec_cx_pkt_kind kind; /**< packet variant */
    173   union {
    174     struct {
    175       void *buf; /**< compressed data buffer */
    176       size_t sz; /**< length of compressed data */
    177       /*!\brief time stamp to show frame (in timebase units) */
    178       vpx_codec_pts_t pts;
    179       /*!\brief duration to show frame (in timebase units) */
    180       unsigned long duration;
    181       vpx_codec_frame_flags_t flags; /**< flags for this frame */
    182       /*!\brief the partition id defines the decoding order of the partitions.
    183        * Only applicable when "output partition" mode is enabled. First
    184        * partition has id 0.*/
    185       int partition_id;
    186     } frame;                            /**< data for compressed frame packet */
    187     vpx_fixed_buf_t twopass_stats;      /**< data for two-pass packet */
    188     vpx_fixed_buf_t firstpass_mb_stats; /**< first pass mb packet */
    189     struct vpx_psnr_pkt {
    190       unsigned int samples[4]; /**< Number of samples, total/y/u/v */
    191       uint64_t sse[4];         /**< sum squared error, total/y/u/v */
    192       double psnr[4];          /**< PSNR, total/y/u/v */
    193     } psnr;                    /**< data for PSNR packet */
    194     vpx_fixed_buf_t raw;       /**< data for arbitrary packets */
    195 // Spatial SVC is still experimental and may be removed before the next
    196 // ABI bump.
    197 #if VPX_ENCODER_ABI_VERSION > (5 + VPX_CODEC_ABI_VERSION)
    198     size_t layer_sizes[VPX_SS_MAX_LAYERS];
    199     struct vpx_psnr_pkt layer_psnr[VPX_SS_MAX_LAYERS];
    200 #endif
    201 
    202     /* This packet size is fixed to allow codecs to extend this
    203      * interface without having to manage storage for raw packets,
    204      * i.e., if it's smaller than 128 bytes, you can store in the
    205      * packet list directly.
    206      */
    207     char pad[128 - sizeof(enum vpx_codec_cx_pkt_kind)]; /**< fixed sz */
    208   } data;                                               /**< packet data */
    209 } vpx_codec_cx_pkt_t; /**< alias for struct vpx_codec_cx_pkt */
    210 
    211 /*!\brief Encoder return output buffer callback
    212  *
    213  * This callback function, when registered, returns with packets when each
    214  * spatial layer is encoded.
    215  */
    216 // putting the definitions here for now. (agrange: find if there
    217 // is a better place for this)
    218 typedef void (*vpx_codec_enc_output_cx_pkt_cb_fn_t)(vpx_codec_cx_pkt_t *pkt,
    219                                                     void *user_data);
    220 
    221 /*!\brief Callback function pointer / user data pair storage */
    222 typedef struct vpx_codec_enc_output_cx_cb_pair {
    223   vpx_codec_enc_output_cx_pkt_cb_fn_t output_cx_pkt; /**< Callback function */
    224   void *user_priv; /**< Pointer to private data */
    225 } vpx_codec_priv_output_cx_pkt_cb_pair_t;
    226 
    227 /*!\brief Rational Number
    228  *
    229  * This structure holds a fractional value.
    230  */
    231 typedef struct vpx_rational {
    232   int num;        /**< fraction numerator */
    233   int den;        /**< fraction denominator */
    234 } vpx_rational_t; /**< alias for struct vpx_rational */
    235 
    236 /*!\brief Multi-pass Encoding Pass */
    237 enum vpx_enc_pass {
    238   VPX_RC_ONE_PASS,   /**< Single pass mode */
    239   VPX_RC_FIRST_PASS, /**< First pass of multi-pass mode */
    240   VPX_RC_LAST_PASS   /**< Final pass of multi-pass mode */
    241 };
    242 
    243 /*!\brief Rate control mode */
    244 enum vpx_rc_mode {
    245   VPX_VBR, /**< Variable Bit Rate (VBR) mode */
    246   VPX_CBR, /**< Constant Bit Rate (CBR) mode */
    247   VPX_CQ,  /**< Constrained Quality (CQ)  mode */
    248   VPX_Q,   /**< Constant Quality (Q) mode */
    249 };
    250 
    251 /*!\brief Keyframe placement mode.
    252  *
    253  * This enumeration determines whether keyframes are placed automatically by
    254  * the encoder or whether this behavior is disabled. Older releases of this
    255  * SDK were implemented such that VPX_KF_FIXED meant keyframes were disabled.
    256  * This name is confusing for this behavior, so the new symbols to be used
    257  * are VPX_KF_AUTO and VPX_KF_DISABLED.
    258  */
    259 enum vpx_kf_mode {
    260   VPX_KF_FIXED,       /**< deprecated, implies VPX_KF_DISABLED */
    261   VPX_KF_AUTO,        /**< Encoder determines optimal placement automatically */
    262   VPX_KF_DISABLED = 0 /**< Encoder does not place keyframes. */
    263 };
    264 
    265 /*!\brief Encoded Frame Flags
    266  *
    267  * This type indicates a bitfield to be passed to vpx_codec_encode(), defining
    268  * per-frame boolean values. By convention, bits common to all codecs will be
    269  * named VPX_EFLAG_*, and bits specific to an algorithm will be named
    270  * /algo/_eflag_*. The lower order 16 bits are reserved for common use.
    271  */
    272 typedef long vpx_enc_frame_flags_t;
    273 #define VPX_EFLAG_FORCE_KF (1 << 0) /**< Force this frame to be a keyframe */
    274 
    275 /*!\brief Encoder configuration structure
    276  *
    277  * This structure contains the encoder settings that have common representations
    278  * across all codecs. This doesn't imply that all codecs support all features,
    279  * however.
    280  */
    281 typedef struct vpx_codec_enc_cfg {
    282   /*
    283    * generic settings (g)
    284    */
    285 
    286   /*!\brief Algorithm specific "usage" value
    287    *
    288    * Algorithms may define multiple values for usage, which may convey the
    289    * intent of how the application intends to use the stream. If this value
    290    * is non-zero, consult the documentation for the codec to determine its
    291    * meaning.
    292    */
    293   unsigned int g_usage;
    294 
    295   /*!\brief Maximum number of threads to use
    296    *
    297    * For multi-threaded implementations, use no more than this number of
    298    * threads. The codec may use fewer threads than allowed. The value
    299    * 0 is equivalent to the value 1.
    300    */
    301   unsigned int g_threads;
    302 
    303   /*!\brief Bitstream profile to use
    304    *
    305    * Some codecs support a notion of multiple bitstream profiles. Typically
    306    * this maps to a set of features that are turned on or off. Often the
    307    * profile to use is determined by the features of the intended decoder.
    308    * Consult the documentation for the codec to determine the valid values
    309    * for this parameter, or set to zero for a sane default.
    310    */
    311   unsigned int g_profile; /**< profile of bitstream to use */
    312 
    313   /*!\brief Width of the frame
    314    *
    315    * This value identifies the presentation resolution of the frame,
    316    * in pixels. Note that the frames passed as input to the encoder must
    317    * have this resolution. Frames will be presented by the decoder in this
    318    * resolution, independent of any spatial resampling the encoder may do.
    319    */
    320   unsigned int g_w;
    321 
    322   /*!\brief Height of the frame
    323    *
    324    * This value identifies the presentation resolution of the frame,
    325    * in pixels. Note that the frames passed as input to the encoder must
    326    * have this resolution. Frames will be presented by the decoder in this
    327    * resolution, independent of any spatial resampling the encoder may do.
    328    */
    329   unsigned int g_h;
    330 
    331   /*!\brief Bit-depth of the codec
    332    *
    333    * This value identifies the bit_depth of the codec,
    334    * Only certain bit-depths are supported as identified in the
    335    * vpx_bit_depth_t enum.
    336    */
    337   vpx_bit_depth_t g_bit_depth;
    338 
    339   /*!\brief Bit-depth of the input frames
    340    *
    341    * This value identifies the bit_depth of the input frames in bits.
    342    * Note that the frames passed as input to the encoder must have
    343    * this bit-depth.
    344    */
    345   unsigned int g_input_bit_depth;
    346 
    347   /*!\brief Stream timebase units
    348    *
    349    * Indicates the smallest interval of time, in seconds, used by the stream.
    350    * For fixed frame rate material, or variable frame rate material where
    351    * frames are timed at a multiple of a given clock (ex: video capture),
    352    * the \ref RECOMMENDED method is to set the timebase to the reciprocal
    353    * of the frame rate (ex: 1001/30000 for 29.970 Hz NTSC). This allows the
    354    * pts to correspond to the frame number, which can be handy. For
    355    * re-encoding video from containers with absolute time timestamps, the
    356    * \ref RECOMMENDED method is to set the timebase to that of the parent
    357    * container or multimedia framework (ex: 1/1000 for ms, as in FLV).
    358    */
    359   struct vpx_rational g_timebase;
    360 
    361   /*!\brief Enable error resilient modes.
    362    *
    363    * The error resilient bitfield indicates to the encoder which features
    364    * it should enable to take measures for streaming over lossy or noisy
    365    * links.
    366    */
    367   vpx_codec_er_flags_t g_error_resilient;
    368 
    369   /*!\brief Multi-pass Encoding Mode
    370    *
    371    * This value should be set to the current phase for multi-pass encoding.
    372    * For single pass, set to #VPX_RC_ONE_PASS.
    373    */
    374   enum vpx_enc_pass g_pass;
    375 
    376   /*!\brief Allow lagged encoding
    377    *
    378    * If set, this value allows the encoder to consume a number of input
    379    * frames before producing output frames. This allows the encoder to
    380    * base decisions for the current frame on future frames. This does
    381    * increase the latency of the encoding pipeline, so it is not appropriate
    382    * in all situations (ex: realtime encoding).
    383    *
    384    * Note that this is a maximum value -- the encoder may produce frames
    385    * sooner than the given limit. Set this value to 0 to disable this
    386    * feature.
    387    */
    388   unsigned int g_lag_in_frames;
    389 
    390   /*
    391    * rate control settings (rc)
    392    */
    393 
    394   /*!\brief Temporal resampling configuration, if supported by the codec.
    395    *
    396    * Temporal resampling allows the codec to "drop" frames as a strategy to
    397    * meet its target data rate. This can cause temporal discontinuities in
    398    * the encoded video, which may appear as stuttering during playback. This
    399    * trade-off is often acceptable, but for many applications is not. It can
    400    * be disabled in these cases.
    401    *
    402    * Note that not all codecs support this feature. All vpx VPx codecs do.
    403    * For other codecs, consult the documentation for that algorithm.
    404    *
    405    * This threshold is described as a percentage of the target data buffer.
    406    * When the data buffer falls below this percentage of fullness, a
    407    * dropped frame is indicated. Set the threshold to zero (0) to disable
    408    * this feature.
    409    */
    410   unsigned int rc_dropframe_thresh;
    411 
    412   /*!\brief Enable/disable spatial resampling, if supported by the codec.
    413    *
    414    * Spatial resampling allows the codec to compress a lower resolution
    415    * version of the frame, which is then upscaled by the encoder to the
    416    * correct presentation resolution. This increases visual quality at
    417    * low data rates, at the expense of CPU time on the encoder/decoder.
    418    */
    419   unsigned int rc_resize_allowed;
    420 
    421   /*!\brief Internal coded frame width.
    422    *
    423    * If spatial resampling is enabled this specifies the width of the
    424    * encoded frame.
    425    */
    426   unsigned int rc_scaled_width;
    427 
    428   /*!\brief Internal coded frame height.
    429    *
    430    * If spatial resampling is enabled this specifies the height of the
    431    * encoded frame.
    432    */
    433   unsigned int rc_scaled_height;
    434 
    435   /*!\brief Spatial resampling up watermark.
    436    *
    437    * This threshold is described as a percentage of the target data buffer.
    438    * When the data buffer rises above this percentage of fullness, the
    439    * encoder will step up to a higher resolution version of the frame.
    440    */
    441   unsigned int rc_resize_up_thresh;
    442 
    443   /*!\brief Spatial resampling down watermark.
    444    *
    445    * This threshold is described as a percentage of the target data buffer.
    446    * When the data buffer falls below this percentage of fullness, the
    447    * encoder will step down to a lower resolution version of the frame.
    448    */
    449   unsigned int rc_resize_down_thresh;
    450 
    451   /*!\brief Rate control algorithm to use.
    452    *
    453    * Indicates whether the end usage of this stream is to be streamed over
    454    * a bandwidth constrained link, indicating that Constant Bit Rate (CBR)
    455    * mode should be used, or whether it will be played back on a high
    456    * bandwidth link, as from a local disk, where higher variations in
    457    * bitrate are acceptable.
    458    */
    459   enum vpx_rc_mode rc_end_usage;
    460 
    461   /*!\brief Two-pass stats buffer.
    462    *
    463    * A buffer containing all of the stats packets produced in the first
    464    * pass, concatenated.
    465    */
    466   vpx_fixed_buf_t rc_twopass_stats_in;
    467 
    468   /*!\brief first pass mb stats buffer.
    469    *
    470    * A buffer containing all of the first pass mb stats packets produced
    471    * in the first pass, concatenated.
    472    */
    473   vpx_fixed_buf_t rc_firstpass_mb_stats_in;
    474 
    475   /*!\brief Target data rate
    476    *
    477    * Target bandwidth to use for this stream, in kilobits per second.
    478    */
    479   unsigned int rc_target_bitrate;
    480 
    481   /*
    482    * quantizer settings
    483    */
    484 
    485   /*!\brief Minimum (Best Quality) Quantizer
    486    *
    487    * The quantizer is the most direct control over the quality of the
    488    * encoded image. The range of valid values for the quantizer is codec
    489    * specific. Consult the documentation for the codec to determine the
    490    * values to use. To determine the range programmatically, call
    491    * vpx_codec_enc_config_default() with a usage value of 0.
    492    */
    493   unsigned int rc_min_quantizer;
    494 
    495   /*!\brief Maximum (Worst Quality) Quantizer
    496    *
    497    * The quantizer is the most direct control over the quality of the
    498    * encoded image. The range of valid values for the quantizer is codec
    499    * specific. Consult the documentation for the codec to determine the
    500    * values to use. To determine the range programmatically, call
    501    * vpx_codec_enc_config_default() with a usage value of 0.
    502    */
    503   unsigned int rc_max_quantizer;
    504 
    505   /*
    506    * bitrate tolerance
    507    */
    508 
    509   /*!\brief Rate control adaptation undershoot control
    510    *
    511    * This value, expressed as a percentage of the target bitrate,
    512    * controls the maximum allowed adaptation speed of the codec.
    513    * This factor controls the maximum amount of bits that can
    514    * be subtracted from the target bitrate in order to compensate
    515    * for prior overshoot.
    516    *
    517    * Valid values in the range 0-1000.
    518    */
    519   unsigned int rc_undershoot_pct;
    520 
    521   /*!\brief Rate control adaptation overshoot control
    522    *
    523    * This value, expressed as a percentage of the target bitrate,
    524    * controls the maximum allowed adaptation speed of the codec.
    525    * This factor controls the maximum amount of bits that can
    526    * be added to the target bitrate in order to compensate for
    527    * prior undershoot.
    528    *
    529    * Valid values in the range 0-1000.
    530    */
    531   unsigned int rc_overshoot_pct;
    532 
    533   /*
    534    * decoder buffer model parameters
    535    */
    536 
    537   /*!\brief Decoder Buffer Size
    538    *
    539    * This value indicates the amount of data that may be buffered by the
    540    * decoding application. Note that this value is expressed in units of
    541    * time (milliseconds). For example, a value of 5000 indicates that the
    542    * client will buffer (at least) 5000ms worth of encoded data. Use the
    543    * target bitrate (#rc_target_bitrate) to convert to bits/bytes, if
    544    * necessary.
    545    */
    546   unsigned int rc_buf_sz;
    547 
    548   /*!\brief Decoder Buffer Initial Size
    549    *
    550    * This value indicates the amount of data that will be buffered by the
    551    * decoding application prior to beginning playback. This value is
    552    * expressed in units of time (milliseconds). Use the target bitrate
    553    * (#rc_target_bitrate) to convert to bits/bytes, if necessary.
    554    */
    555   unsigned int rc_buf_initial_sz;
    556 
    557   /*!\brief Decoder Buffer Optimal Size
    558    *
    559    * This value indicates the amount of data that the encoder should try
    560    * to maintain in the decoder's buffer. This value is expressed in units
    561    * of time (milliseconds). Use the target bitrate (#rc_target_bitrate)
    562    * to convert to bits/bytes, if necessary.
    563    */
    564   unsigned int rc_buf_optimal_sz;
    565 
    566   /*
    567    * 2 pass rate control parameters
    568    */
    569 
    570   /*!\brief Two-pass mode CBR/VBR bias
    571    *
    572    * Bias, expressed on a scale of 0 to 100, for determining target size
    573    * for the current frame. The value 0 indicates the optimal CBR mode
    574    * value should be used. The value 100 indicates the optimal VBR mode
    575    * value should be used. Values in between indicate which way the
    576    * encoder should "lean."
    577    */
    578   unsigned int rc_2pass_vbr_bias_pct;
    579 
    580   /*!\brief Two-pass mode per-GOP minimum bitrate
    581    *
    582    * This value, expressed as a percentage of the target bitrate, indicates
    583    * the minimum bitrate to be used for a single GOP (aka "section")
    584    */
    585   unsigned int rc_2pass_vbr_minsection_pct;
    586 
    587   /*!\brief Two-pass mode per-GOP maximum bitrate
    588    *
    589    * This value, expressed as a percentage of the target bitrate, indicates
    590    * the maximum bitrate to be used for a single GOP (aka "section")
    591    */
    592   unsigned int rc_2pass_vbr_maxsection_pct;
    593 
    594   /*
    595    * keyframing settings (kf)
    596    */
    597 
    598   /*!\brief Keyframe placement mode
    599    *
    600    * This value indicates whether the encoder should place keyframes at a
    601    * fixed interval, or determine the optimal placement automatically
    602    * (as governed by the #kf_min_dist and #kf_max_dist parameters)
    603    */
    604   enum vpx_kf_mode kf_mode;
    605 
    606   /*!\brief Keyframe minimum interval
    607    *
    608    * This value, expressed as a number of frames, prevents the encoder from
    609    * placing a keyframe nearer than kf_min_dist to the previous keyframe. At
    610    * least kf_min_dist frames non-keyframes will be coded before the next
    611    * keyframe. Set kf_min_dist equal to kf_max_dist for a fixed interval.
    612    */
    613   unsigned int kf_min_dist;
    614 
    615   /*!\brief Keyframe maximum interval
    616    *
    617    * This value, expressed as a number of frames, forces the encoder to code
    618    * a keyframe if one has not been coded in the last kf_max_dist frames.
    619    * A value of 0 implies all frames will be keyframes. Set kf_min_dist
    620    * equal to kf_max_dist for a fixed interval.
    621    */
    622   unsigned int kf_max_dist;
    623 
    624   /*
    625    * Spatial scalability settings (ss)
    626    */
    627 
    628   /*!\brief Number of spatial coding layers.
    629    *
    630    * This value specifies the number of spatial coding layers to be used.
    631    */
    632   unsigned int ss_number_layers;
    633 
    634   /*!\brief Enable auto alt reference flags for each spatial layer.
    635    *
    636    * These values specify if auto alt reference frame is enabled for each
    637    * spatial layer.
    638    */
    639   int ss_enable_auto_alt_ref[VPX_SS_MAX_LAYERS];
    640 
    641   /*!\brief Target bitrate for each spatial layer.
    642    *
    643    * These values specify the target coding bitrate to be used for each
    644    * spatial layer.
    645    */
    646   unsigned int ss_target_bitrate[VPX_SS_MAX_LAYERS];
    647 
    648   /*!\brief Number of temporal coding layers.
    649    *
    650    * This value specifies the number of temporal layers to be used.
    651    */
    652   unsigned int ts_number_layers;
    653 
    654   /*!\brief Target bitrate for each temporal layer.
    655    *
    656    * These values specify the target coding bitrate to be used for each
    657    * temporal layer.
    658    */
    659   unsigned int ts_target_bitrate[VPX_TS_MAX_LAYERS];
    660 
    661   /*!\brief Frame rate decimation factor for each temporal layer.
    662    *
    663    * These values specify the frame rate decimation factors to apply
    664    * to each temporal layer.
    665    */
    666   unsigned int ts_rate_decimator[VPX_TS_MAX_LAYERS];
    667 
    668   /*!\brief Length of the sequence defining frame temporal layer membership.
    669    *
    670    * This value specifies the length of the sequence that defines the
    671    * membership of frames to temporal layers. For example, if the
    672    * ts_periodicity = 8, then the frames are assigned to coding layers with a
    673    * repeated sequence of length 8.
    674   */
    675   unsigned int ts_periodicity;
    676 
    677   /*!\brief Template defining the membership of frames to temporal layers.
    678    *
    679    * This array defines the membership of frames to temporal coding layers.
    680    * For a 2-layer encoding that assigns even numbered frames to one temporal
    681    * layer (0) and odd numbered frames to a second temporal layer (1) with
    682    * ts_periodicity=8, then ts_layer_id = (0,1,0,1,0,1,0,1).
    683   */
    684   unsigned int ts_layer_id[VPX_TS_MAX_PERIODICITY];
    685 
    686   /*!\brief Target bitrate for each spatial/temporal layer.
    687    *
    688    * These values specify the target coding bitrate to be used for each
    689    * spatial/temporal layer.
    690    *
    691    */
    692   unsigned int layer_target_bitrate[VPX_MAX_LAYERS];
    693 
    694   /*!\brief Temporal layering mode indicating which temporal layering scheme to
    695    * use.
    696    *
    697    * The value (refer to VP9E_TEMPORAL_LAYERING_MODE) specifies the
    698    * temporal layering mode to use.
    699    *
    700    */
    701   int temporal_layering_mode;
    702 } vpx_codec_enc_cfg_t; /**< alias for struct vpx_codec_enc_cfg */
    703 
    704 /*!\brief  vp9 svc extra configure parameters
    705  *
    706  * This defines max/min quantizers and scale factors for each layer
    707  *
    708  */
    709 typedef struct vpx_svc_parameters {
    710   int max_quantizers[VPX_MAX_LAYERS];     /**< Max Q for each layer */
    711   int min_quantizers[VPX_MAX_LAYERS];     /**< Min Q for each layer */
    712   int scaling_factor_num[VPX_MAX_LAYERS]; /**< Scaling factor-numerator */
    713   int scaling_factor_den[VPX_MAX_LAYERS]; /**< Scaling factor-denominator */
    714   int speed_per_layer[VPX_MAX_LAYERS];    /**< Speed setting for each sl */
    715   int temporal_layering_mode;             /**< Temporal layering mode */
    716 } vpx_svc_extra_cfg_t;
    717 
    718 /*!\brief Initialize an encoder instance
    719  *
    720  * Initializes a encoder context using the given interface. Applications
    721  * should call the vpx_codec_enc_init convenience macro instead of this
    722  * function directly, to ensure that the ABI version number parameter
    723  * is properly initialized.
    724  *
    725  * If the library was configured with --disable-multithread, this call
    726  * is not thread safe and should be guarded with a lock if being used
    727  * in a multithreaded context.
    728  *
    729  * \param[in]    ctx     Pointer to this instance's context.
    730  * \param[in]    iface   Pointer to the algorithm interface to use.
    731  * \param[in]    cfg     Configuration to use, if known. May be NULL.
    732  * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
    733  * \param[in]    ver     ABI version number. Must be set to
    734  *                       VPX_ENCODER_ABI_VERSION
    735  * \retval #VPX_CODEC_OK
    736  *     The decoder algorithm initialized.
    737  * \retval #VPX_CODEC_MEM_ERROR
    738  *     Memory allocation failed.
    739  */
    740 vpx_codec_err_t vpx_codec_enc_init_ver(vpx_codec_ctx_t *ctx,
    741                                        vpx_codec_iface_t *iface,
    742                                        const vpx_codec_enc_cfg_t *cfg,
    743                                        vpx_codec_flags_t flags, int ver);
    744 
    745 /*!\brief Convenience macro for vpx_codec_enc_init_ver()
    746  *
    747  * Ensures the ABI version parameter is properly set.
    748  */
    749 #define vpx_codec_enc_init(ctx, iface, cfg, flags) \
    750   vpx_codec_enc_init_ver(ctx, iface, cfg, flags, VPX_ENCODER_ABI_VERSION)
    751 
    752 /*!\brief Initialize multi-encoder instance
    753  *
    754  * Initializes multi-encoder context using the given interface.
    755  * Applications should call the vpx_codec_enc_init_multi convenience macro
    756  * instead of this function directly, to ensure that the ABI version number
    757  * parameter is properly initialized.
    758  *
    759  * \param[in]    ctx     Pointer to this instance's context.
    760  * \param[in]    iface   Pointer to the algorithm interface to use.
    761  * \param[in]    cfg     Configuration to use, if known. May be NULL.
    762  * \param[in]    num_enc Total number of encoders.
    763  * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
    764  * \param[in]    dsf     Pointer to down-sampling factors.
    765  * \param[in]    ver     ABI version number. Must be set to
    766  *                       VPX_ENCODER_ABI_VERSION
    767  * \retval #VPX_CODEC_OK
    768  *     The decoder algorithm initialized.
    769  * \retval #VPX_CODEC_MEM_ERROR
    770  *     Memory allocation failed.
    771  */
    772 vpx_codec_err_t vpx_codec_enc_init_multi_ver(
    773     vpx_codec_ctx_t *ctx, vpx_codec_iface_t *iface, vpx_codec_enc_cfg_t *cfg,
    774     int num_enc, vpx_codec_flags_t flags, vpx_rational_t *dsf, int ver);
    775 
    776 /*!\brief Convenience macro for vpx_codec_enc_init_multi_ver()
    777  *
    778  * Ensures the ABI version parameter is properly set.
    779  */
    780 #define vpx_codec_enc_init_multi(ctx, iface, cfg, num_enc, flags, dsf) \
    781   vpx_codec_enc_init_multi_ver(ctx, iface, cfg, num_enc, flags, dsf,   \
    782                                VPX_ENCODER_ABI_VERSION)
    783 
    784 /*!\brief Get a default configuration
    785  *
    786  * Initializes a encoder configuration structure with default values. Supports
    787  * the notion of "usages" so that an algorithm may offer different default
    788  * settings depending on the user's intended goal. This function \ref SHOULD
    789  * be called by all applications to initialize the configuration structure
    790  * before specializing the configuration with application specific values.
    791  *
    792  * \param[in]    iface     Pointer to the algorithm interface to use.
    793  * \param[out]   cfg       Configuration buffer to populate.
    794  * \param[in]    reserved  Must set to 0 for VP8 and VP9.
    795  *
    796  * \retval #VPX_CODEC_OK
    797  *     The configuration was populated.
    798  * \retval #VPX_CODEC_INCAPABLE
    799  *     Interface is not an encoder interface.
    800  * \retval #VPX_CODEC_INVALID_PARAM
    801  *     A parameter was NULL, or the usage value was not recognized.
    802  */
    803 vpx_codec_err_t vpx_codec_enc_config_default(vpx_codec_iface_t *iface,
    804                                              vpx_codec_enc_cfg_t *cfg,
    805                                              unsigned int reserved);
    806 
    807 /*!\brief Set or change configuration
    808  *
    809  * Reconfigures an encoder instance according to the given configuration.
    810  *
    811  * \param[in]    ctx     Pointer to this instance's context
    812  * \param[in]    cfg     Configuration buffer to use
    813  *
    814  * \retval #VPX_CODEC_OK
    815  *     The configuration was populated.
    816  * \retval #VPX_CODEC_INCAPABLE
    817  *     Interface is not an encoder interface.
    818  * \retval #VPX_CODEC_INVALID_PARAM
    819  *     A parameter was NULL, or the usage value was not recognized.
    820  */
    821 vpx_codec_err_t vpx_codec_enc_config_set(vpx_codec_ctx_t *ctx,
    822                                          const vpx_codec_enc_cfg_t *cfg);
    823 
    824 /*!\brief Get global stream headers
    825  *
    826  * Retrieves a stream level global header packet, if supported by the codec.
    827  *
    828  * \param[in]    ctx     Pointer to this instance's context
    829  *
    830  * \retval NULL
    831  *     Encoder does not support global header
    832  * \retval Non-NULL
    833  *     Pointer to buffer containing global header packet
    834  */
    835 vpx_fixed_buf_t *vpx_codec_get_global_headers(vpx_codec_ctx_t *ctx);
    836 
    837 /*!\brief deadline parameter analogous to VPx REALTIME mode. */
    838 #define VPX_DL_REALTIME (1)
    839 /*!\brief deadline parameter analogous to  VPx GOOD QUALITY mode. */
    840 #define VPX_DL_GOOD_QUALITY (1000000)
    841 /*!\brief deadline parameter analogous to VPx BEST QUALITY mode. */
    842 #define VPX_DL_BEST_QUALITY (0)
    843 /*!\brief Encode a frame
    844  *
    845  * Encodes a video frame at the given "presentation time." The presentation
    846  * time stamp (PTS) \ref MUST be strictly increasing.
    847  *
    848  * The encoder supports the notion of a soft real-time deadline. Given a
    849  * non-zero value to the deadline parameter, the encoder will make a "best
    850  * effort" guarantee to  return before the given time slice expires. It is
    851  * implicit that limiting the available time to encode will degrade the
    852  * output quality. The encoder can be given an unlimited time to produce the
    853  * best possible frame by specifying a deadline of '0'. This deadline
    854  * supercedes the VPx notion of "best quality, good quality, realtime".
    855  * Applications that wish to map these former settings to the new deadline
    856  * based system can use the symbols #VPX_DL_REALTIME, #VPX_DL_GOOD_QUALITY,
    857  * and #VPX_DL_BEST_QUALITY.
    858  *
    859  * When the last frame has been passed to the encoder, this function should
    860  * continue to be called, with the img parameter set to NULL. This will
    861  * signal the end-of-stream condition to the encoder and allow it to encode
    862  * any held buffers. Encoding is complete when vpx_codec_encode() is called
    863  * and vpx_codec_get_cx_data() returns no data.
    864  *
    865  * \param[in]    ctx       Pointer to this instance's context
    866  * \param[in]    img       Image data to encode, NULL to flush.
    867  * \param[in]    pts       Presentation time stamp, in timebase units.
    868  * \param[in]    duration  Duration to show frame, in timebase units.
    869  * \param[in]    flags     Flags to use for encoding this frame.
    870  * \param[in]    deadline  Time to spend encoding, in microseconds. (0=infinite)
    871  *
    872  * \retval #VPX_CODEC_OK
    873  *     The configuration was populated.
    874  * \retval #VPX_CODEC_INCAPABLE
    875  *     Interface is not an encoder interface.
    876  * \retval #VPX_CODEC_INVALID_PARAM
    877  *     A parameter was NULL, the image format is unsupported, etc.
    878  */
    879 vpx_codec_err_t vpx_codec_encode(vpx_codec_ctx_t *ctx, const vpx_image_t *img,
    880                                  vpx_codec_pts_t pts, unsigned long duration,
    881                                  vpx_enc_frame_flags_t flags,
    882                                  unsigned long deadline);
    883 
    884 /*!\brief Set compressed data output buffer
    885  *
    886  * Sets the buffer that the codec should output the compressed data
    887  * into. This call effectively sets the buffer pointer returned in the
    888  * next VPX_CODEC_CX_FRAME_PKT packet. Subsequent packets will be
    889  * appended into this buffer. The buffer is preserved across frames,
    890  * so applications must periodically call this function after flushing
    891  * the accumulated compressed data to disk or to the network to reset
    892  * the pointer to the buffer's head.
    893  *
    894  * `pad_before` bytes will be skipped before writing the compressed
    895  * data, and `pad_after` bytes will be appended to the packet. The size
    896  * of the packet will be the sum of the size of the actual compressed
    897  * data, pad_before, and pad_after. The padding bytes will be preserved
    898  * (not overwritten).
    899  *
    900  * Note that calling this function does not guarantee that the returned
    901  * compressed data will be placed into the specified buffer. In the
    902  * event that the encoded data will not fit into the buffer provided,
    903  * the returned packet \ref MAY point to an internal buffer, as it would
    904  * if this call were never used. In this event, the output packet will
    905  * NOT have any padding, and the application must free space and copy it
    906  * to the proper place. This is of particular note in configurations
    907  * that may output multiple packets for a single encoded frame (e.g., lagged
    908  * encoding) or if the application does not reset the buffer periodically.
    909  *
    910  * Applications may restore the default behavior of the codec providing
    911  * the compressed data buffer by calling this function with a NULL
    912  * buffer.
    913  *
    914  * Applications \ref MUSTNOT call this function during iteration of
    915  * vpx_codec_get_cx_data().
    916  *
    917  * \param[in]    ctx         Pointer to this instance's context
    918  * \param[in]    buf         Buffer to store compressed data into
    919  * \param[in]    pad_before  Bytes to skip before writing compressed data
    920  * \param[in]    pad_after   Bytes to skip after writing compressed data
    921  *
    922  * \retval #VPX_CODEC_OK
    923  *     The buffer was set successfully.
    924  * \retval #VPX_CODEC_INVALID_PARAM
    925  *     A parameter was NULL, the image format is unsupported, etc.
    926  */
    927 vpx_codec_err_t vpx_codec_set_cx_data_buf(vpx_codec_ctx_t *ctx,
    928                                           const vpx_fixed_buf_t *buf,
    929                                           unsigned int pad_before,
    930                                           unsigned int pad_after);
    931 
    932 /*!\brief Encoded data iterator
    933  *
    934  * Iterates over a list of data packets to be passed from the encoder to the
    935  * application. The different kinds of packets available are enumerated in
    936  * #vpx_codec_cx_pkt_kind.
    937  *
    938  * #VPX_CODEC_CX_FRAME_PKT packets should be passed to the application's
    939  * muxer. Multiple compressed frames may be in the list.
    940  * #VPX_CODEC_STATS_PKT packets should be appended to a global buffer.
    941  *
    942  * The application \ref MUST silently ignore any packet kinds that it does
    943  * not recognize or support.
    944  *
    945  * The data buffers returned from this function are only guaranteed to be
    946  * valid until the application makes another call to any vpx_codec_* function.
    947  *
    948  * \param[in]     ctx      Pointer to this instance's context
    949  * \param[in,out] iter     Iterator storage, initialized to NULL
    950  *
    951  * \return Returns a pointer to an output data packet (compressed frame data,
    952  *         two-pass statistics, etc.) or NULL to signal end-of-list.
    953  *
    954  */
    955 const vpx_codec_cx_pkt_t *vpx_codec_get_cx_data(vpx_codec_ctx_t *ctx,
    956                                                 vpx_codec_iter_t *iter);
    957 
    958 /*!\brief Get Preview Frame
    959  *
    960  * Returns an image that can be used as a preview. Shows the image as it would
    961  * exist at the decompressor. The application \ref MUST NOT write into this
    962  * image buffer.
    963  *
    964  * \param[in]     ctx      Pointer to this instance's context
    965  *
    966  * \return Returns a pointer to a preview image, or NULL if no image is
    967  *         available.
    968  *
    969  */
    970 const vpx_image_t *vpx_codec_get_preview_frame(vpx_codec_ctx_t *ctx);
    971 
    972 /*!@} - end defgroup encoder*/
    973 #ifdef __cplusplus
    974 }
    975 #endif
    976 #endif  // VPX_VPX_ENCODER_H_
    977