aom/vpx/vpx_image.h

/*
 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */


/*!\file
 * \brief Describes the vpx image descriptor and associated operations
 *
 */
#ifndef VPX_VPX_IMAGE_H_
#define VPX_VPX_IMAGE_H_

#ifdef __cplusplus
extern "C" {
#endif

  /*!\brief Current ABI version number
   *
   * \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
   */
#define VPX_IMAGE_ABI_VERSION (2) /**<\hideinitializer*/


#define VPX_IMG_FMT_PLANAR     0x100  /**< Image is a planar format. */
#define VPX_IMG_FMT_UV_FLIP    0x200  /**< V plane precedes U in memory. */
#define VPX_IMG_FMT_HAS_ALPHA  0x400  /**< Image has an alpha channel. */
#define VPX_IMG_FMT_HIGHBITDEPTH 0x800  /**< Image uses 16bit framebuffer. */

  /*!\brief List of supported image formats */
  typedef enum vpx_img_fmt {
    VPX_IMG_FMT_NONE,
    VPX_IMG_FMT_RGB24,   /**< 24 bit per pixel packed RGB */
    VPX_IMG_FMT_RGB32,   /**< 32 bit per pixel packed 0RGB */
    VPX_IMG_FMT_RGB565,  /**< 16 bit per pixel, 565 */
    VPX_IMG_FMT_RGB555,  /**< 16 bit per pixel, 555 */
    VPX_IMG_FMT_UYVY,    /**< UYVY packed YUV */
    VPX_IMG_FMT_YUY2,    /**< YUYV packed YUV */
    VPX_IMG_FMT_YVYU,    /**< YVYU packed YUV */
    VPX_IMG_FMT_BGR24,   /**< 24 bit per pixel packed BGR */
    VPX_IMG_FMT_RGB32_LE, /**< 32 bit packed BGR0 */
    VPX_IMG_FMT_ARGB,     /**< 32 bit packed ARGB, alpha=255 */
    VPX_IMG_FMT_ARGB_LE,  /**< 32 bit packed BGRA, alpha=255 */
    VPX_IMG_FMT_RGB565_LE,  /**< 16 bit per pixel, gggbbbbb rrrrrggg */
    VPX_IMG_FMT_RGB555_LE,  /**< 16 bit per pixel, gggbbbbb 0rrrrrgg */
    VPX_IMG_FMT_YV12    = VPX_IMG_FMT_PLANAR | VPX_IMG_FMT_UV_FLIP | 1, /**< planar YVU */
    VPX_IMG_FMT_I420    = VPX_IMG_FMT_PLANAR | 2,
    VPX_IMG_FMT_VPXYV12 = VPX_IMG_FMT_PLANAR | VPX_IMG_FMT_UV_FLIP | 3, /** < planar 4:2:0 format with vpx color space */
    VPX_IMG_FMT_VPXI420 = VPX_IMG_FMT_PLANAR | 4,
    VPX_IMG_FMT_I422    = VPX_IMG_FMT_PLANAR | 5,
    VPX_IMG_FMT_I444    = VPX_IMG_FMT_PLANAR | 6,
    VPX_IMG_FMT_444A    = VPX_IMG_FMT_PLANAR | VPX_IMG_FMT_HAS_ALPHA | 7,
    VPX_IMG_FMT_I42016    = VPX_IMG_FMT_I420 | VPX_IMG_FMT_HIGHBITDEPTH,
    VPX_IMG_FMT_I42216    = VPX_IMG_FMT_I422 | VPX_IMG_FMT_HIGHBITDEPTH,
    VPX_IMG_FMT_I44416    = VPX_IMG_FMT_I444 | VPX_IMG_FMT_HIGHBITDEPTH
  } vpx_img_fmt_t; /**< alias for enum vpx_img_fmt */

  /**\brief Image Descriptor */
  typedef struct vpx_image {
    vpx_img_fmt_t fmt; /**< Image Format */

    /* Image storage dimensions */
    unsigned int  w;           /**< Stored image width */
    unsigned int  h;           /**< Stored image height */
    unsigned int  bit_depth;   /**< Stored image bit-depth */

    /* Image display dimensions */
    unsigned int  d_w;   /**< Displayed image width */
    unsigned int  d_h;   /**< Displayed image height */

    /* Chroma subsampling info */
    unsigned int  x_chroma_shift;   /**< subsampling order, X */
    unsigned int  y_chroma_shift;   /**< subsampling order, Y */

    /* Image data pointers. */
#define VPX_PLANE_PACKED 0   /**< To be used for all packed formats */
#define VPX_PLANE_Y      0   /**< Y (Luminance) plane */
#define VPX_PLANE_U      1   /**< U (Chroma) plane */
#define VPX_PLANE_V      2   /**< V (Chroma) plane */
#define VPX_PLANE_ALPHA  3   /**< A (Transparency) plane */
    unsigned char *planes[4];  /**< pointer to the top left pixel for each plane */
    int      stride[4];  /**< stride between rows for each plane */

    int     bps; /**< bits per sample (for packed formats) */

    /* The following member may be set by the application to associate data
     * with this image.
     */
    void    *user_priv; /**< may be set by the application to associate data
                         *   with this image. */

    /* The following members should be treated as private. */
    unsigned char *img_data;       /**< private */
    int      img_data_owner; /**< private */
    int      self_allocd;    /**< private */

    void    *fb_priv; /**< Frame buffer data associated with the image. */
  } vpx_image_t; /**< alias for struct vpx_image */

  /**\brief Representation of a rectangle on a surface */
  typedef struct vpx_image_rect {
    unsigned int x; /**< leftmost column */
    unsigned int y; /**< topmost row */
    unsigned int w; /**< width */
    unsigned int h; /**< height */
  } vpx_image_rect_t; /**< alias for struct vpx_image_rect */

  /*!\brief Open a descriptor, allocating storage for the underlying image
   *
   * Returns a descriptor for storing an image of the given format. The
   * storage for the descriptor is allocated on the heap.
   *
   * \param[in]    img       Pointer to storage for descriptor. If this parameter
   *                         is NULL, the storage for the descriptor will be
   *                         allocated on the heap.
   * \param[in]    fmt       Format for the image
   * \param[in]    d_w       Width of the image
   * \param[in]    d_h       Height of the image
   * \param[in]    align     Alignment, in bytes, of the image buffer and
   *                         each row in the image(stride).
   *
   * \return Returns a pointer to the initialized image descriptor. If the img
   *         parameter is non-null, the value of the img parameter will be
   *         returned.
   */
  vpx_image_t *vpx_img_alloc(vpx_image_t  *img,
                             vpx_img_fmt_t fmt,
                             unsigned int d_w,
                             unsigned int d_h,
                             unsigned int align);

  /*!\brief Open a descriptor, using existing storage for the underlying image
   *
   * Returns a descriptor for storing an image of the given format. The
   * storage for descriptor has been allocated elsewhere, and a descriptor is
   * desired to "wrap" that storage.
   *
   * \param[in]    img       Pointer to storage for descriptor. If this parameter
   *                         is NULL, the storage for the descriptor will be
   *                         allocated on the heap.
   * \param[in]    fmt       Format for the image
   * \param[in]    d_w       Width of the image
   * \param[in]    d_h       Height of the image
   * \param[in]    align     Alignment, in bytes, of each row in the image.
   * \param[in]    img_data  Storage to use for the image
   *
   * \return Returns a pointer to the initialized image descriptor. If the img
   *         parameter is non-null, the value of the img parameter will be
   *         returned.
   */
  vpx_image_t *vpx_img_wrap(vpx_image_t  *img,
                            vpx_img_fmt_t fmt,
                            unsigned int d_w,
                            unsigned int d_h,
                            unsigned int align,
                            unsigned char      *img_data);


  /*!\brief Set the rectangle identifying the displayed portion of the image
   *
   * Updates the displayed rectangle (aka viewport) on the image surface to
   * match the specified coordinates and size.
   *
   * \param[in]    img       Image descriptor
   * \param[in]    x         leftmost column
   * \param[in]    y         topmost row
   * \param[in]    w         width
   * \param[in]    h         height
   *
   * \return 0 if the requested rectangle is valid, nonzero otherwise.
   */
  int vpx_img_set_rect(vpx_image_t  *img,
                       unsigned int  x,
                       unsigned int  y,
                       unsigned int  w,
                       unsigned int  h);


  /*!\brief Flip the image vertically (top for bottom)
   *
   * Adjusts the image descriptor's pointers and strides to make the image
   * be referenced upside-down.
   *
   * \param[in]    img       Image descriptor
   */
  void vpx_img_flip(vpx_image_t *img);

  /*!\brief Close an image descriptor
   *
   * Frees all allocated storage associated with an image descriptor.
   *
   * \param[in]    img       Image descriptor
   */
  void vpx_img_free(vpx_image_t *img);

#ifdef __cplusplus
}  // extern "C"
#endif

#endif  // VPX_VPX_IMAGE_H_