include/vlc_picture.h

   1 /*****************************************************************************
   2  * vlc_picture.h: picture definitions
   3  *****************************************************************************
   4  * Copyright (C) 1999 - 2009 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Vincent Seguin <seguin@via.ecp.fr>
   8  *          Samuel Hocevar <sam@via.ecp.fr>
   9  *          Olivier Aubert <oaubert 47 videolan d07 org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this program; if not, write to the Free Software Foundation,
  23  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 #ifndef VLC_PICTURE_H
  27 #define VLC_PICTURE_H 1
  28
  29 #include <assert.h>
  30
  31 /**
  32  * \file
  33  * This file defines picture structures and functions in vlc
  34  */
  35
  36 #include <vlc_es.h>
  37
  38 /** Description of a planar graphic field */
  39 typedef struct plane_t
  40 {
  41     uint8_t *p_pixels;                        /**< Start of the plane's data */
  42
  43     /* Variables used for fast memcpy operations */
  44     int i_lines;           /**< Number of lines, including margins */
  45     int i_pitch;           /**< Number of bytes in a line, including margins */
  46
  47     /** Size of a macropixel, defaults to 1 */
  48     int i_pixel_pitch;
  49
  50     /* Variables used for pictures with margins */
  51     int i_visible_lines;            /**< How many visible lines are there ? */
  52     int i_visible_pitch;            /**< How many visible pixels are there ? */
  53
  54 } plane_t;
  55
  56 /**
  57  * Maximum number of plane for a picture
  58  */
  59 #define PICTURE_PLANE_MAX (VOUT_MAX_PLANES)
  60
  61 typedef struct picture_context_t
  62 {
  63     void (*destroy)(struct picture_context_t *);
  64     struct picture_context_t *(*copy)(struct picture_context_t *);
  65 } picture_context_t;
  66
  67 /**
  68  * Video picture
  69  */
  70 struct picture_t
  71 {
  72     /**
  73      * The properties of the picture
  74      */
  75     video_frame_format_t format;
  76
  77     plane_t         p[PICTURE_PLANE_MAX];     /**< description of the planes */
  78     int             i_planes;                /**< number of allocated planes */
  79
  80     /** \name Picture management properties
  81      * These properties can be modified using the video output thread API,
  82      * but should never be written directly */
  83     /**@{*/
  84     mtime_t         date;                                  /**< display date */
  85     bool            b_force;
  86     /**@}*/
  87
  88     /** \name Picture dynamic properties
  89      * Those properties can be changed by the decoder
  90      * @{
  91      */
  92     bool            b_progressive;          /**< is it a progressive frame ? */
  93     bool            b_top_field_first;             /**< which field is first */
  94     unsigned int    i_nb_fields;                  /**< # of displayed fields */
  95     picture_context_t *context;      /**< video format-specific data pointer */
  96     /**@}*/
  97
  98     /** Private data - the video output plugin might want to put stuff here to
  99      * keep track of the picture */
 100     picture_sys_t * p_sys;
 101
 102     /** Next picture in a FIFO a pictures */
 103     struct picture_t *p_next;
 104 };
 105
 106 /**
 107  * This function will create a new picture.
 108  * The picture created will implement a default release management compatible
 109  * with picture_Hold and picture_Release. This default management will release
 110  * p_sys, gc.p_sys fields if non NULL.
 111  */
 112 VLC_API picture_t * picture_New( vlc_fourcc_t i_chroma, int i_width, int i_height, int i_sar_num, int i_sar_den ) VLC_USED;
 113
 114 /**
 115  * This function will create a new picture using the given format.
 116  *
 117  * When possible, it is preferred to use this function over picture_New
 118  * as more information about the format is kept.
 119  */
 120 VLC_API picture_t * picture_NewFromFormat( const video_format_t *p_fmt ) VLC_USED;
 121
 122 /**
 123  * Resource for a picture.
 124  */
 125 typedef struct
 126 {
 127     picture_sys_t *p_sys;
 128     void (*pf_destroy)(picture_t *);
 129
 130     /* Plane resources
 131      * XXX all fields MUST be set to the right value.
 132      */
 133     struct
 134     {
 135         uint8_t *p_pixels;  /**< Start of the plane's data */
 136         int i_lines;        /**< Number of lines, including margins */
 137         int i_pitch;        /**< Number of bytes in a line, including margins */
 138     } p[PICTURE_PLANE_MAX];
 139
 140 } picture_resource_t;
 141
 142 /**
 143  * This function will create a new picture using the provided resource.
 144  *
 145  * If the resource is NULL then a plain picture_NewFromFormat is returned.
 146  */
 147 VLC_API picture_t * picture_NewFromResource( const video_format_t *, const picture_resource_t * ) VLC_USED;
 148
 149 /**
 150  * This function will increase the picture reference count.
 151  * It will not have any effect on picture obtained from vout
 152  *
 153  * It returns the given picture for convenience.
 154  */
 155 VLC_API picture_t *picture_Hold( picture_t *p_picture );
 156
 157 /**
 158  * This function will release a picture.
 159  * It will not have any effect on picture obtained from vout
 160  */
 161 VLC_API void picture_Release( picture_t *p_picture );
 162
 163 /**
 164  * This function will copy all picture dynamic properties.
 165  */
 166 VLC_API void picture_CopyProperties( picture_t *p_dst, const picture_t *p_src );
 167
 168 /**
 169  * This function will reset a picture information (properties and quantizers).
 170  * It is sometimes useful for reusing pictures (like from a pool).
 171  */
 172 VLC_API void picture_Reset( picture_t * );
 173
 174 /**
 175  * This function will copy the picture pixels.
 176  * You can safely copy between pictures that do not have the same size,
 177  * only the compatible(smaller) part will be copied.
 178  */
 179 VLC_API void picture_CopyPixels( picture_t *p_dst, const picture_t *p_src );
 180 VLC_API void plane_CopyPixels( plane_t *p_dst, const plane_t *p_src );
 181
 182 /**
 183  * This function will copy both picture dynamic properties and pixels.
 184  * You have to notice that sometime a simple picture_Hold may do what
 185  * you want without the copy overhead.
 186  * Provided for convenience.
 187  *
 188  * \param p_dst pointer to the destination picture.
 189  * \param p_src pointer to the source picture.
 190  */
 191 VLC_API void picture_Copy( picture_t *p_dst, const picture_t *p_src );
 192
 193 /**
 194  * Perform a shallow picture copy
 195  *
 196  * This function makes a shallow copy of an existing picture. The same planes
 197  * and resources will be used, and the cloned picture reference count will be
 198  * incremented.
 199  *
 200  * \return A clone picture on success, NULL on error.
 201  */
 202 VLC_API picture_t *picture_Clone(picture_t *pic);
 203
 204 /**
 205  * This function will export a picture to an encoded bitstream.
 206  *
 207  * pp_image will contain the encoded bitstream in psz_format format.
 208  *
 209  * p_fmt can be NULL otherwise it will be set with the format used for the
 210  * picture before encoding.
 211  *
 212  * i_override_width/height allow to override the width and/or the height of the
 213  * picture to be encoded:
 214  *  - if strictly lower than 0, the original dimension will be used.
 215  *  - if equal to 0, it will be deduced from the other dimension which must be
 216  *  different to 0.
 217  *  - if strictly higher than 0, it will override the dimension.
 218  * If at most one of them is > 0 then the picture aspect ratio will be kept.
 219  */
 220 VLC_API int picture_Export( vlc_object_t *p_obj, block_t **pp_image, video_format_t *p_fmt, picture_t *p_picture, vlc_fourcc_t i_format, int i_override_width, int i_override_height );
 221
 222 /**
 223  * This function will setup all fields of a picture_t without allocating any
 224  * memory.
 225  * XXX The memory must already be initialized.
 226  * It does not need to be released.
 227  *
 228  * It will return VLC_EGENERIC if the core does not understand the requested
 229  * format.
 230  *
 231  * It can be useful to get the properties of planes.
 232  */
 233 VLC_API int picture_Setup( picture_t *, const video_format_t * );
 234
 235
 236 /*****************************************************************************
 237  * Shortcuts to access image components
 238  *****************************************************************************/
 239
 240 /* Plane indices */
 241 enum
 242 {
 243     Y_PLANE = 0,
 244     U_PLANE = 1,
 245     V_PLANE = 2,
 246     A_PLANE = 3,
 247 };
 248
 249 /* Shortcuts */
 250 #define Y_PIXELS     p[Y_PLANE].p_pixels
 251 #define Y_PITCH      p[Y_PLANE].i_pitch
 252 #define U_PIXELS     p[U_PLANE].p_pixels
 253 #define U_PITCH      p[U_PLANE].i_pitch
 254 #define V_PIXELS     p[V_PLANE].p_pixels
 255 #define V_PITCH      p[V_PLANE].i_pitch
 256 #define A_PIXELS     p[A_PLANE].p_pixels
 257 #define A_PITCH      p[A_PLANE].i_pitch
 258
 259 /**
 260  * Swap UV planes of a Tri Planars picture.
 261  *
 262  * It just swap the planes information without doing any copy.
 263  */
 264 static inline void picture_SwapUV(picture_t *picture)
 265 {
 266     assert(picture->i_planes == 3);
 267
 268     plane_t tmp_plane   = picture->p[U_PLANE];
 269     picture->p[U_PLANE] = picture->p[V_PLANE];
 270     picture->p[V_PLANE] = tmp_plane;
 271 }
 272
 273 /**@}*/
 274
 275 #endif /* VLC_PICTURE_H */