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 typedef struct picture_buffer_t
  68 {
  69     int fd;
  70     void *base;
  71     size_t size;
  72     off_t offset;
  73 } picture_buffer_t;
  74
  75 /**
  76  * Video picture
  77  */
  78 struct picture_t
  79 {
  80     /**
  81      * The properties of the picture
  82      */
  83     video_frame_format_t format;
  84
  85     plane_t         p[PICTURE_PLANE_MAX];     /**< description of the planes */
  86     int             i_planes;                /**< number of allocated planes */
  87
  88     /** \name Picture management properties
  89      * These properties can be modified using the video output thread API,
  90      * but should never be written directly */
  91     /**@{*/
  92     vlc_tick_t      date;                                  /**< display date */
  93     bool            b_force;
  94     bool            b_still;
  95     /**@}*/
  96
  97     /** \name Picture dynamic properties
  98      * Those properties can be changed by the decoder
  99      * @{
 100      */
 101     bool            b_progressive;          /**< is it a progressive frame? */
 102     bool            b_top_field_first;             /**< which field is first */
 103     unsigned int    i_nb_fields;                  /**< number of displayed fields */
 104     picture_context_t *context;      /**< video format-specific data pointer */
 105     /**@}*/
 106
 107     /** Private data - the video output plugin might want to put stuff here to
 108      * keep track of the picture */
 109     void           *p_sys;
 110
 111     /** Next picture in a FIFO a pictures */
 112     struct picture_t *p_next;
 113 };
 114
 115 /**
 116  * This function will create a new picture.
 117  * The picture created will implement a default release management compatible
 118  * with picture_Hold and picture_Release. This default management will release
 119  * p_sys, gc.p_sys fields if non NULL.
 120  */
 121 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;
 122
 123 /**
 124  * This function will create a new picture using the given format.
 125  *
 126  * When possible, it is preferred to use this function over picture_New
 127  * as more information about the format is kept.
 128  */
 129 VLC_API picture_t * picture_NewFromFormat( const video_format_t *p_fmt ) VLC_USED;
 130
 131 /**
 132  * Resource for a picture.
 133  */
 134 typedef struct
 135 {
 136     void *p_sys;
 137     void (*pf_destroy)(picture_t *);
 138
 139     /* Plane resources
 140      * XXX all fields MUST be set to the right value.
 141      */
 142     struct
 143     {
 144         uint8_t *p_pixels;  /**< Start of the plane's data */
 145         int i_lines;        /**< Number of lines, including margins */
 146         int i_pitch;        /**< Number of bytes in a line, including margins */
 147     } p[PICTURE_PLANE_MAX];
 148
 149 } picture_resource_t;
 150
 151 /**
 152  * This function will create a new picture using the provided resource.
 153  *
 154  * If the resource is NULL then a plain picture_NewFromFormat is returned.
 155  */
 156 VLC_API picture_t * picture_NewFromResource( const video_format_t *, const picture_resource_t * ) VLC_USED;
 157
 158 /**
 159  * This function will increase the picture reference count.
 160  * It will not have any effect on picture obtained from vout
 161  *
 162  * It returns the given picture for convenience.
 163  */
 164 VLC_API picture_t *picture_Hold( picture_t *p_picture );
 165
 166 /**
 167  * This function will release a picture.
 168  * It will not have any effect on picture obtained from vout
 169  */
 170 VLC_API void picture_Release( picture_t *p_picture );
 171
 172 /**
 173  * This function will copy all picture dynamic properties.
 174  */
 175 VLC_API void picture_CopyProperties( picture_t *p_dst, const picture_t *p_src );
 176
 177 /**
 178  * This function will reset a picture information (properties and quantizers).
 179  * It is sometimes useful for reusing pictures (like from a pool).
 180  */
 181 VLC_API void picture_Reset( picture_t * );
 182
 183 /**
 184  * This function will copy the picture pixels.
 185  * You can safely copy between pictures that do not have the same size,
 186  * only the compatible(smaller) part will be copied.
 187  */
 188 VLC_API void picture_CopyPixels( picture_t *p_dst, const picture_t *p_src );
 189 VLC_API void plane_CopyPixels( plane_t *p_dst, const plane_t *p_src );
 190
 191 /**
 192  * This function will copy both picture dynamic properties and pixels.
 193  * You have to notice that sometime a simple picture_Hold may do what
 194  * you want without the copy overhead.
 195  * Provided for convenience.
 196  *
 197  * \param p_dst pointer to the destination picture.
 198  * \param p_src pointer to the source picture.
 199  */
 200 VLC_API void picture_Copy( picture_t *p_dst, const picture_t *p_src );
 201
 202 /**
 203  * Perform a shallow picture copy
 204  *
 205  * This function makes a shallow copy of an existing picture. The same planes
 206  * and resources will be used, and the cloned picture reference count will be
 207  * incremented.
 208  *
 209  * \return A clone picture on success, NULL on error.
 210  */
 211 VLC_API picture_t *picture_Clone(picture_t *pic);
 212
 213 /**
 214  * This function will export a picture to an encoded bitstream.
 215  *
 216  * pp_image will contain the encoded bitstream in psz_format format.
 217  *
 218  * p_fmt can be NULL otherwise it will be set with the format used for the
 219  * picture before encoding.
 220  *
 221  * i_override_width/height allow to override the width and/or the height of the
 222  * picture to be encoded:
 223  *  - if strictly lower than 0, the original dimension will be used.
 224  *  - if equal to 0, it will be deduced from the other dimension which must be
 225  *  different to 0.
 226  *  - if strictly higher than 0, it will override the dimension.
 227  * If at most one of them is > 0 then the picture aspect ratio will be kept.
 228  */
 229 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 );
 230
 231 /**
 232  * This function will setup all fields of a picture_t without allocating any
 233  * memory.
 234  * XXX The memory must already be initialized.
 235  * It does not need to be released.
 236  *
 237  * It will return VLC_EGENERIC if the core does not understand the requested
 238  * format.
 239  *
 240  * It can be useful to get the properties of planes.
 241  */
 242 VLC_API int picture_Setup( picture_t *, const video_format_t * );
 243
 244
 245 /*****************************************************************************
 246  * Shortcuts to access image components
 247  *****************************************************************************/
 248
 249 /* Plane indices */
 250 enum
 251 {
 252     Y_PLANE = 0,
 253     U_PLANE = 1,
 254     V_PLANE = 2,
 255     A_PLANE = 3,
 256 };
 257
 258 /* Shortcuts */
 259 #define Y_PIXELS     p[Y_PLANE].p_pixels
 260 #define Y_PITCH      p[Y_PLANE].i_pitch
 261 #define U_PIXELS     p[U_PLANE].p_pixels
 262 #define U_PITCH      p[U_PLANE].i_pitch
 263 #define V_PIXELS     p[V_PLANE].p_pixels
 264 #define V_PITCH      p[V_PLANE].i_pitch
 265 #define A_PIXELS     p[A_PLANE].p_pixels
 266 #define A_PITCH      p[A_PLANE].i_pitch
 267
 268 /**
 269  * Swap UV planes of a Tri Planars picture.
 270  *
 271  * It just swap the planes information without doing any copy.
 272  */
 273 static inline void picture_SwapUV(picture_t *picture)
 274 {
 275     vlc_assert(picture->i_planes == 3);
 276
 277     plane_t tmp_plane   = picture->p[U_PLANE];
 278     picture->p[U_PLANE] = picture->p[V_PLANE];
 279     picture->p[V_PLANE] = tmp_plane;
 280 }
 281
 282 /**@}*/
 283
 284 #endif /* VLC_PICTURE_H */