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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 
     11 /*!\defgroup codec Common Algorithm Interface
     12  * This abstraction allows applications to easily support multiple video
     13  * formats with minimal code duplication. This section describes the interface
     14  * common to all codecs (both encoders and decoders).
     15  * @{
     16  */
     17 
     18 /*!\file
     19  * \brief Describes the codec algorithm interface to applications.
     20  *
     21  * This file describes the interface between an application and a
     22  * video codec algorithm.
     23  *
     24  * An application instantiates a specific codec instance by using
     25  * vpx_codec_init() and a pointer to the algorithm's interface structure:
     26  *     <pre>
     27  *     my_app.c:
     28  *       extern vpx_codec_iface_t my_codec;
     29  *       {
     30  *           vpx_codec_ctx_t algo;
     31  *           res = vpx_codec_init(&algo, &my_codec);
     32  *       }
     33  *     </pre>
     34  *
     35  * Once initialized, the instance is manged using other functions from
     36  * the vpx_codec_* family.
     37  */
     38 #ifndef VPX_VPX_CODEC_H_
     39 #define VPX_VPX_CODEC_H_
     40 
     41 #ifdef __cplusplus
     42 extern "C" {
     43 #endif
     44 
     45 #include "./vpx_image.h"
     46 #include "./vpx_integer.h"
     47 
     48 /*!\brief Decorator indicating a function is deprecated */
     49 #ifndef VPX_DEPRECATED
     50 #if defined(__GNUC__) && __GNUC__
     51 #define VPX_DEPRECATED __attribute__((deprecated))
     52 #elif defined(_MSC_VER)
     53 #define VPX_DEPRECATED
     54 #else
     55 #define VPX_DEPRECATED
     56 #endif
     57 #endif /* VPX_DEPRECATED */
     58 
     59 #ifndef VPX_DECLSPEC_DEPRECATED
     60 #if defined(__GNUC__) && __GNUC__
     61 #define VPX_DECLSPEC_DEPRECATED /**< \copydoc #VPX_DEPRECATED */
     62 #elif defined(_MSC_VER)
     63 /*!\brief \copydoc #VPX_DEPRECATED */
     64 #define VPX_DECLSPEC_DEPRECATED __declspec(deprecated)
     65 #else
     66 #define VPX_DECLSPEC_DEPRECATED /**< \copydoc #VPX_DEPRECATED */
     67 #endif
     68 #endif /* VPX_DECLSPEC_DEPRECATED */
     69 
     70 /*!\brief Decorator indicating a function is potentially unused */
     71 #ifndef VPX_UNUSED
     72 #if defined(__GNUC__) || defined(__clang__)
     73 #define VPX_UNUSED __attribute__((unused))
     74 #else
     75 #define VPX_UNUSED
     76 #endif
     77 #endif /* VPX_UNUSED */
     78 
     79 /*!\brief Current ABI version number
     80  *
     81  * \internal
     82  * If this file is altered in any way that changes the ABI, this value
     83  * must be bumped.  Examples include, but are not limited to, changing
     84  * types, removing or reassigning enums, adding/removing/rearranging
     85  * fields to structures
     86  */
     87 #define VPX_CODEC_ABI_VERSION (4 + VPX_IMAGE_ABI_VERSION) /**<\hideinitializer*/
     88 
     89 /*!\brief Algorithm return codes */
     90 typedef enum {
     91   /*!\brief Operation completed without error */
     92   VPX_CODEC_OK,
     93 
     94   /*!\brief Unspecified error */
     95   VPX_CODEC_ERROR,
     96 
     97   /*!\brief Memory operation failed */
     98   VPX_CODEC_MEM_ERROR,
     99 
    100   /*!\brief ABI version mismatch */
    101   VPX_CODEC_ABI_MISMATCH,
    102 
    103   /*!\brief Algorithm does not have required capability */
    104   VPX_CODEC_INCAPABLE,
    105 
    106   /*!\brief The given bitstream is not supported.
    107    *
    108    * The bitstream was unable to be parsed at the highest level. The decoder
    109    * is unable to proceed. This error \ref SHOULD be treated as fatal to the
    110    * stream. */
    111   VPX_CODEC_UNSUP_BITSTREAM,
    112 
    113   /*!\brief Encoded bitstream uses an unsupported feature
    114    *
    115    * The decoder does not implement a feature required by the encoder. This
    116    * return code should only be used for features that prevent future
    117    * pictures from being properly decoded. This error \ref MAY be treated as
    118    * fatal to the stream or \ref MAY be treated as fatal to the current GOP.
    119    */
    120   VPX_CODEC_UNSUP_FEATURE,
    121 
    122   /*!\brief The coded data for this stream is corrupt or incomplete
    123    *
    124    * There was a problem decoding the current frame.  This return code
    125    * should only be used for failures that prevent future pictures from
    126    * being properly decoded. This error \ref MAY be treated as fatal to the
    127    * stream or \ref MAY be treated as fatal to the current GOP. If decoding
    128    * is continued for the current GOP, artifacts may be present.
    129    */
    130   VPX_CODEC_CORRUPT_FRAME,
    131 
    132   /*!\brief An application-supplied parameter is not valid.
    133    *
    134    */
    135   VPX_CODEC_INVALID_PARAM,
    136 
    137   /*!\brief An iterator reached the end of list.
    138    *
    139    */
    140   VPX_CODEC_LIST_END
    141 
    142 } vpx_codec_err_t;
    143 
    144 /*! \brief Codec capabilities bitfield
    145  *
    146  *  Each codec advertises the capabilities it supports as part of its
    147  *  ::vpx_codec_iface_t interface structure. Capabilities are extra interfaces
    148  *  or functionality, and are not required to be supported.
    149  *
    150  *  The available flags are specified by VPX_CODEC_CAP_* defines.
    151  */
    152 typedef long vpx_codec_caps_t;
    153 #define VPX_CODEC_CAP_DECODER 0x1 /**< Is a decoder */
    154 #define VPX_CODEC_CAP_ENCODER 0x2 /**< Is an encoder */
    155 
    156 /*! Can support images at greater than 8 bitdepth.
    157  */
    158 #define VPX_CODEC_CAP_HIGHBITDEPTH 0x4
    159 
    160 /*! \brief Initialization-time Feature Enabling
    161  *
    162  *  Certain codec features must be known at initialization time, to allow for
    163  *  proper memory allocation.
    164  *
    165  *  The available flags are specified by VPX_CODEC_USE_* defines.
    166  */
    167 typedef long vpx_codec_flags_t;
    168 
    169 /*!\brief Codec interface structure.
    170  *
    171  * Contains function pointers and other data private to the codec
    172  * implementation. This structure is opaque to the application.
    173  */
    174 typedef const struct vpx_codec_iface vpx_codec_iface_t;
    175 
    176 /*!\brief Codec private data structure.
    177  *
    178  * Contains data private to the codec implementation. This structure is opaque
    179  * to the application.
    180  */
    181 typedef struct vpx_codec_priv vpx_codec_priv_t;
    182 
    183 /*!\brief Iterator
    184  *
    185  * Opaque storage used for iterating over lists.
    186  */
    187 typedef const void *vpx_codec_iter_t;
    188 
    189 /*!\brief Codec context structure
    190  *
    191  * All codecs \ref MUST support this context structure fully. In general,
    192  * this data should be considered private to the codec algorithm, and
    193  * not be manipulated or examined by the calling application. Applications
    194  * may reference the 'name' member to get a printable description of the
    195  * algorithm.
    196  */
    197 typedef struct vpx_codec_ctx {
    198   const char *name;             /**< Printable interface name */
    199   vpx_codec_iface_t *iface;     /**< Interface pointers */
    200   vpx_codec_err_t err;          /**< Last returned error */
    201   const char *err_detail;       /**< Detailed info, if available */
    202   vpx_codec_flags_t init_flags; /**< Flags passed at init time */
    203   union {
    204     /**< Decoder Configuration Pointer */
    205     const struct vpx_codec_dec_cfg *dec;
    206     /**< Encoder Configuration Pointer */
    207     const struct vpx_codec_enc_cfg *enc;
    208     const void *raw;
    209   } config;               /**< Configuration pointer aliasing union */
    210   vpx_codec_priv_t *priv; /**< Algorithm private storage */
    211 } vpx_codec_ctx_t;
    212 
    213 /*!\brief Bit depth for codec
    214  * *
    215  * This enumeration determines the bit depth of the codec.
    216  */
    217 typedef enum vpx_bit_depth {
    218   VPX_BITS_8 = 8,   /**<  8 bits */
    219   VPX_BITS_10 = 10, /**< 10 bits */
    220   VPX_BITS_12 = 12, /**< 12 bits */
    221 } vpx_bit_depth_t;
    222 
    223 /*
    224  * Library Version Number Interface
    225  *
    226  * For example, see the following sample return values:
    227  *     vpx_codec_version()           (1<<16 | 2<<8 | 3)
    228  *     vpx_codec_version_str()       "v1.2.3-rc1-16-gec6a1ba"
    229  *     vpx_codec_version_extra_str() "rc1-16-gec6a1ba"
    230  */
    231 
    232 /*!\brief Return the version information (as an integer)
    233  *
    234  * Returns a packed encoding of the library version number. This will only
    235  * include
    236  * the major.minor.patch component of the version number. Note that this encoded
    237  * value should be accessed through the macros provided, as the encoding may
    238  * change
    239  * in the future.
    240  *
    241  */
    242 int vpx_codec_version(void);
    243 #define VPX_VERSION_MAJOR(v) \
    244   ((v >> 16) & 0xff) /**< extract major from packed version */
    245 #define VPX_VERSION_MINOR(v) \
    246   ((v >> 8) & 0xff) /**< extract minor from packed version */
    247 #define VPX_VERSION_PATCH(v) \
    248   ((v >> 0) & 0xff) /**< extract patch from packed version */
    249 
    250 /*!\brief Return the version major number */
    251 #define vpx_codec_version_major() ((vpx_codec_version() >> 16) & 0xff)
    252 
    253 /*!\brief Return the version minor number */
    254 #define vpx_codec_version_minor() ((vpx_codec_version() >> 8) & 0xff)
    255 
    256 /*!\brief Return the version patch number */
    257 #define vpx_codec_version_patch() ((vpx_codec_version() >> 0) & 0xff)
    258 
    259 /*!\brief Return the version information (as a string)
    260  *
    261  * Returns a printable string containing the full library version number. This
    262  * may
    263  * contain additional text following the three digit version number, as to
    264  * indicate
    265  * release candidates, prerelease versions, etc.
    266  *
    267  */
    268 const char *vpx_codec_version_str(void);
    269 
    270 /*!\brief Return the version information (as a string)
    271  *
    272  * Returns a printable "extra string". This is the component of the string
    273  * returned
    274  * by vpx_codec_version_str() following the three digit version number.
    275  *
    276  */
    277 const char *vpx_codec_version_extra_str(void);
    278 
    279 /*!\brief Return the build configuration
    280  *
    281  * Returns a printable string containing an encoded version of the build
    282  * configuration. This may be useful to vpx support.
    283  *
    284  */
    285 const char *vpx_codec_build_config(void);
    286 
    287 /*!\brief Return the name for a given interface
    288  *
    289  * Returns a human readable string for name of the given codec interface.
    290  *
    291  * \param[in]    iface     Interface pointer
    292  *
    293  */
    294 const char *vpx_codec_iface_name(vpx_codec_iface_t *iface);
    295 
    296 /*!\brief Convert error number to printable string
    297  *
    298  * Returns a human readable string for the last error returned by the
    299  * algorithm. The returned error will be one line and will not contain
    300  * any newline characters.
    301  *
    302  *
    303  * \param[in]    err     Error number.
    304  *
    305  */
    306 const char *vpx_codec_err_to_string(vpx_codec_err_t err);
    307 
    308 /*!\brief Retrieve error synopsis for codec context
    309  *
    310  * Returns a human readable string for the last error returned by the
    311  * algorithm. The returned error will be one line and will not contain
    312  * any newline characters.
    313  *
    314  *
    315  * \param[in]    ctx     Pointer to this instance's context.
    316  *
    317  */
    318 const char *vpx_codec_error(vpx_codec_ctx_t *ctx);
    319 
    320 /*!\brief Retrieve detailed error information for codec context
    321  *
    322  * Returns a human readable string providing detailed information about
    323  * the last error.
    324  *
    325  * \param[in]    ctx     Pointer to this instance's context.
    326  *
    327  * \retval NULL
    328  *     No detailed information is available.
    329  */
    330 const char *vpx_codec_error_detail(vpx_codec_ctx_t *ctx);
    331 
    332 /* REQUIRED FUNCTIONS
    333  *
    334  * The following functions are required to be implemented for all codecs.
    335  * They represent the base case functionality expected of all codecs.
    336  */
    337 
    338 /*!\brief Destroy a codec instance
    339  *
    340  * Destroys a codec context, freeing any associated memory buffers.
    341  *
    342  * \param[in] ctx   Pointer to this instance's context
    343  *
    344  * \retval #VPX_CODEC_OK
    345  *     The codec algorithm initialized.
    346  * \retval #VPX_CODEC_MEM_ERROR
    347  *     Memory allocation failed.
    348  */
    349 vpx_codec_err_t vpx_codec_destroy(vpx_codec_ctx_t *ctx);
    350 
    351 /*!\brief Get the capabilities of an algorithm.
    352  *
    353  * Retrieves the capabilities bitfield from the algorithm's interface.
    354  *
    355  * \param[in] iface   Pointer to the algorithm interface
    356  *
    357  */
    358 vpx_codec_caps_t vpx_codec_get_caps(vpx_codec_iface_t *iface);
    359 
    360 /*!\brief Control algorithm
    361  *
    362  * This function is used to exchange algorithm specific data with the codec
    363  * instance. This can be used to implement features specific to a particular
    364  * algorithm.
    365  *
    366  * This wrapper function dispatches the request to the helper function
    367  * associated with the given ctrl_id. It tries to call this function
    368  * transparently, but will return #VPX_CODEC_ERROR if the request could not
    369  * be dispatched.
    370  *
    371  * Note that this function should not be used directly. Call the
    372  * #vpx_codec_control wrapper macro instead.
    373  *
    374  * \param[in]     ctx              Pointer to this instance's context
    375  * \param[in]     ctrl_id          Algorithm specific control identifier
    376  *
    377  * \retval #VPX_CODEC_OK
    378  *     The control request was processed.
    379  * \retval #VPX_CODEC_ERROR
    380  *     The control request was not processed.
    381  * \retval #VPX_CODEC_INVALID_PARAM
    382  *     The data was not valid.
    383  */
    384 vpx_codec_err_t vpx_codec_control_(vpx_codec_ctx_t *ctx, int ctrl_id, ...);
    385 #if defined(VPX_DISABLE_CTRL_TYPECHECKS) && VPX_DISABLE_CTRL_TYPECHECKS
    386 #define vpx_codec_control(ctx, id, data) vpx_codec_control_(ctx, id, data)
    387 #define VPX_CTRL_USE_TYPE(id, typ)
    388 #define VPX_CTRL_USE_TYPE_DEPRECATED(id, typ)
    389 #define VPX_CTRL_VOID(id, typ)
    390 
    391 #else
    392 /*!\brief vpx_codec_control wrapper macro
    393  *
    394  * This macro allows for type safe conversions across the variadic parameter
    395  * to vpx_codec_control_().
    396  *
    397  * \internal
    398  * It works by dispatching the call to the control function through a wrapper
    399  * function named with the id parameter.
    400  */
    401 #define vpx_codec_control(ctx, id, data) \
    402   vpx_codec_control_##id(ctx, id, data) /**<\hideinitializer*/
    403 
    404 /*!\brief vpx_codec_control type definition macro
    405  *
    406  * This macro allows for type safe conversions across the variadic parameter
    407  * to vpx_codec_control_(). It defines the type of the argument for a given
    408  * control identifier.
    409  *
    410  * \internal
    411  * It defines a static function with
    412  * the correctly typed arguments as a wrapper to the type-unsafe internal
    413  * function.
    414  */
    415 #define VPX_CTRL_USE_TYPE(id, typ)                                           \
    416   static vpx_codec_err_t vpx_codec_control_##id(vpx_codec_ctx_t *, int, typ) \
    417       VPX_UNUSED;                                                            \
    418                                                                              \
    419   static vpx_codec_err_t vpx_codec_control_##id(vpx_codec_ctx_t *ctx,        \
    420                                                 int ctrl_id, typ data) {     \
    421     return vpx_codec_control_(ctx, ctrl_id, data);                           \
    422   } /**<\hideinitializer*/
    423 
    424 /*!\brief vpx_codec_control deprecated type definition macro
    425  *
    426  * Like #VPX_CTRL_USE_TYPE, but indicates that the specified control is
    427  * deprecated and should not be used. Consult the documentation for your
    428  * codec for more information.
    429  *
    430  * \internal
    431  * It defines a static function with the correctly typed arguments as a
    432  * wrapper to the type-unsafe internal function.
    433  */
    434 #define VPX_CTRL_USE_TYPE_DEPRECATED(id, typ)                            \
    435   VPX_DECLSPEC_DEPRECATED static vpx_codec_err_t vpx_codec_control_##id( \
    436       vpx_codec_ctx_t *, int, typ) VPX_DEPRECATED VPX_UNUSED;            \
    437                                                                          \
    438   VPX_DECLSPEC_DEPRECATED static vpx_codec_err_t vpx_codec_control_##id( \
    439       vpx_codec_ctx_t *ctx, int ctrl_id, typ data) {                     \
    440     return vpx_codec_control_(ctx, ctrl_id, data);                       \
    441   } /**<\hideinitializer*/
    442 
    443 /*!\brief vpx_codec_control void type definition macro
    444  *
    445  * This macro allows for type safe conversions across the variadic parameter
    446  * to vpx_codec_control_(). It indicates that a given control identifier takes
    447  * no argument.
    448  *
    449  * \internal
    450  * It defines a static function without a data argument as a wrapper to the
    451  * type-unsafe internal function.
    452  */
    453 #define VPX_CTRL_VOID(id)                                               \
    454   static vpx_codec_err_t vpx_codec_control_##id(vpx_codec_ctx_t *, int) \
    455       VPX_UNUSED;                                                       \
    456                                                                         \
    457   static vpx_codec_err_t vpx_codec_control_##id(vpx_codec_ctx_t *ctx,   \
    458                                                 int ctrl_id) {          \
    459     return vpx_codec_control_(ctx, ctrl_id);                            \
    460   } /**<\hideinitializer*/
    461 
    462 #endif
    463 
    464 /*!@} - end defgroup codec*/
    465 #ifdef __cplusplus
    466 }
    467 #endif
    468 #endif  // VPX_VPX_CODEC_H_
    469