snapshot vout plugin: avoid variables conflicting with the core
[vlc.git] / modules / video_output / snapshot.c
1 /*****************************************************************************
2  * snapshot.c : snapshot plugin for vlc
3  *****************************************************************************
4  * Copyright (C) 2002 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Olivier Aubert <oaubert@lisi.univ-lyon1.fr>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22  *****************************************************************************/
23
24 /*****************************************************************************
25  * This module is a pseudo video output that offers the possibility to
26  * keep a cache of low-res snapshots.
27  * The snapshot structure is defined in include/snapshot.h
28  * In order to access the current snapshot cache, object variables are used:
29  *   vout-snapshot-list-pointer : the pointer on the first element in the list
30  *   vout-snapshot-datasize     : size of a snapshot
31  *                           (also available in snapshot_t->i_datasize)
32  *   vout-snapshot-cache-size   : size of the cache list
33  *
34  * It is used for the moment by the CORBA module and a specialized
35  * python-vlc binding.
36  *****************************************************************************/
37
38 /*****************************************************************************
39  * Preamble
40  *****************************************************************************/
41
42 #ifdef HAVE_CONFIG_H
43 # include "config.h"
44 #endif
45
46 #include <vlc_common.h>
47 #include <vlc_plugin.h>
48 #include <vlc_vout.h>
49 #include <vlc_interface.h>
50 #include <vlc_input.h>
51
52 /*****************************************************************************
53  * Local prototypes
54  *****************************************************************************/
55 static int  Create    ( vlc_object_t * );
56 static void Destroy   ( vlc_object_t * );
57
58 static int  Init      ( vout_thread_t * );
59 static void End       ( vout_thread_t * );
60 static void Display   ( vout_thread_t *, picture_t * );
61
62 /*****************************************************************************
63  * Module descriptor
64  *****************************************************************************/
65 #define WIDTH_TEXT N_( "Snapshot width" )
66 #define WIDTH_LONGTEXT N_( "Width of the snapshot image." )
67
68 #define HEIGHT_TEXT N_( "Snapshot height" )
69 #define HEIGHT_LONGTEXT N_( "Height of the snapshot image." )
70
71 #define CHROMA_TEXT N_( "Chroma" )
72 #define CHROMA_LONGTEXT N_( "Output chroma for the snapshot image " \
73                             "(a 4 character string, like \"RV32\")." )
74
75 #define CACHE_TEXT N_( "Cache size (number of images)" )
76 #define CACHE_LONGTEXT N_( "Snapshot cache size (number of images to keep)." )
77
78
79 vlc_module_begin ()
80     set_description( N_( "Snapshot output" ) )
81     set_shortname( N_("Snapshot") )
82
83     set_category( CAT_VIDEO )
84     set_subcategory( SUBCAT_VIDEO_VOUT )
85     set_capability( "video output", 1 )
86
87     add_integer( "vout-snapshot-width", 320, NULL, WIDTH_TEXT, WIDTH_LONGTEXT, false )
88     add_integer( "vout-snapshot-height", 200, NULL, HEIGHT_TEXT, HEIGHT_LONGTEXT, false )
89     add_string( "vout-snapshot-chroma", "RV32", NULL, CHROMA_TEXT, CHROMA_LONGTEXT, true )
90     add_integer( "vout-snapshot-cache-size", 50, NULL, CACHE_TEXT, CACHE_LONGTEXT, true )
91
92     set_callbacks( Create, Destroy )
93 vlc_module_end ()
94
95 /*****************************************************************************
96  * vout_sys_t: video output descriptor
97  *****************************************************************************/
98 typedef struct snapshot_t
99 {
100   uint8_t *p_data;   /* Data area */
101
102   int i_width;       /* In pixels */
103   int i_height;      /* In pixels */
104   int i_datasize;    /* In bytes */
105   mtime_t date;      /* Presentation time */
106 } snapshot_t;
107
108 struct vout_sys_t
109 {
110     snapshot_t **p_list;    /* List of available snapshots */
111     int i_index;            /* Index of the next available list member */
112     int i_size;             /* Size of the cache */
113     int i_datasize;         /* Size of an image */
114     input_thread_t *p_input;             /* The input thread */
115 };
116
117 /*****************************************************************************
118  * Create: allocates video thread
119  *****************************************************************************
120  * This function allocates and initializes a vout method.
121  *****************************************************************************/
122 static int Create( vlc_object_t *p_this )
123 {
124     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
125
126     /* Allocate instance and initialize some members */
127     p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
128     if( ! p_vout->p_sys )
129         return VLC_ENOMEM;
130
131     var_Create( p_vout, "vout-snapshot-width", VLC_VAR_INTEGER );
132     var_Create( p_vout, "vout-snapshot-height", VLC_VAR_INTEGER );
133     var_Create( p_vout, "vout-snapshot-datasize", VLC_VAR_INTEGER );
134     var_Create( p_vout, "vout-snapshot-cache-size", VLC_VAR_INTEGER );
135     var_Create( p_vout, "vout-snapshot-list-pointer", VLC_VAR_ADDRESS );
136
137     p_vout->pf_init = Init;
138     p_vout->pf_end = End;
139     p_vout->pf_manage = NULL;
140     p_vout->pf_render = NULL;
141     p_vout->pf_display = Display;
142
143     return VLC_SUCCESS;
144 }
145
146 /*****************************************************************************
147  * Init: initialize video thread
148  *****************************************************************************/
149 static int Init( vout_thread_t *p_vout )
150 {
151     int i_index;
152     picture_t *p_pic;
153     vlc_value_t val;
154     char* psz_chroma;
155     int i_chroma;
156     int i_width;
157     int i_height;
158     int i_datasize;
159
160     i_width  = config_GetInt( p_vout, "vout-snapshot-width" );
161     i_height = config_GetInt( p_vout, "vout-snapshot-height" );
162
163     psz_chroma = config_GetPsz( p_vout, "vout-snapshot-chroma" );
164     if( psz_chroma )
165     {
166         if( strlen( psz_chroma ) < 4 )
167         {
168             msg_Err( p_vout, "vout-snapshot-chroma should be 4 characters long" );
169             return VLC_EGENERIC;
170         }
171         i_chroma = VLC_FOURCC( psz_chroma[0], psz_chroma[1],
172                                psz_chroma[2], psz_chroma[3] );
173         free( psz_chroma );
174     }
175     else
176     {
177         msg_Err( p_vout, "Cannot find chroma information." );
178         return VLC_EGENERIC;
179     }
180
181     I_OUTPUTPICTURES = 0;
182
183     /* Initialize the output structure */
184     p_vout->output.i_chroma = i_chroma;
185     p_vout->output.pf_setpalette = NULL;
186     p_vout->output.i_width = i_width;
187     p_vout->output.i_height = i_height;
188     p_vout->output.i_aspect = p_vout->output.i_width
189                                * VOUT_ASPECT_FACTOR / p_vout->output.i_height;
190
191
192     /* Define the bitmasks */
193     switch( i_chroma )
194     {
195       case VLC_FOURCC( 'R','V','1','5' ):
196         p_vout->output.i_rmask = 0x001f;
197         p_vout->output.i_gmask = 0x03e0;
198         p_vout->output.i_bmask = 0x7c00;
199         break;
200
201       case VLC_FOURCC( 'R','V','1','6' ):
202         p_vout->output.i_rmask = 0x001f;
203         p_vout->output.i_gmask = 0x07e0;
204         p_vout->output.i_bmask = 0xf800;
205         break;
206
207       case VLC_FOURCC( 'R','V','2','4' ):
208         p_vout->output.i_rmask = 0xff0000;
209         p_vout->output.i_gmask = 0x00ff00;
210         p_vout->output.i_bmask = 0x0000ff;
211         break;
212
213       case VLC_FOURCC( 'R','V','3','2' ):
214         p_vout->output.i_rmask = 0xff0000;
215         p_vout->output.i_gmask = 0x00ff00;
216         p_vout->output.i_bmask = 0x0000ff;
217         break;
218     }
219
220     /* Try to initialize 1 direct buffer */
221     p_pic = NULL;
222
223     /* Find an empty picture slot */
224     for( i_index = 0 ; i_index < VOUT_MAX_PICTURES ; i_index++ )
225     {
226         if( p_vout->p_picture[ i_index ].i_status == FREE_PICTURE )
227         {
228             p_pic = p_vout->p_picture + i_index;
229             break;
230         }
231     }
232
233     /* Allocate the picture */
234     if( p_pic == NULL )
235     {
236         return VLC_SUCCESS;
237     }
238
239     vout_AllocatePicture( VLC_OBJECT(p_vout), p_pic, p_vout->output.i_chroma,
240                           p_vout->output.i_width, p_vout->output.i_height,
241                           p_vout->output.i_aspect );
242
243     if( p_pic->i_planes == 0 )
244     {
245         return VLC_EGENERIC;
246     }
247
248     p_pic->i_status = DESTROYED_PICTURE;
249     p_pic->i_type   = DIRECT_PICTURE;
250
251     PP_OUTPUTPICTURE[ I_OUTPUTPICTURES ] = p_pic;
252
253     I_OUTPUTPICTURES++;
254
255
256     /* Get datasize and set variables */
257     i_datasize = i_width * i_height * p_pic->p->i_pixel_pitch;
258
259     p_vout->p_sys->i_datasize = i_datasize;
260     p_vout->p_sys->i_index = 0;
261     p_vout->p_sys->i_size = config_GetInt( p_vout, "vout-snapshot-cache-size" );
262
263     if( p_vout->p_sys->i_size < 2 )
264     {
265         msg_Err( p_vout, "vout-snapshot-cache-size must be at least 1." );
266         return VLC_EGENERIC;
267     }
268
269     p_vout->p_sys->p_list = malloc( p_vout->p_sys->i_size * sizeof( snapshot_t * ) );
270
271     if( p_vout->p_sys->p_list == NULL )
272         return VLC_ENOMEM;
273
274     /* Initialize the structures for the circular buffer */
275     for( i_index = 0; i_index < p_vout->p_sys->i_size; i_index++ )
276     {
277         snapshot_t *p_snapshot = malloc( sizeof( snapshot_t ) );
278
279         if( p_snapshot == NULL )
280             return VLC_ENOMEM;
281
282         p_snapshot->i_width = i_width;
283         p_snapshot->i_height = i_height;
284         p_snapshot->i_datasize = i_datasize;
285         p_snapshot->date = 0;
286         p_snapshot->p_data = malloc( i_datasize );
287         if( p_snapshot->p_data == NULL )
288         {
289             free( p_snapshot );
290             return VLC_ENOMEM;
291         }
292         p_vout->p_sys->p_list[i_index] = p_snapshot;
293     }
294
295     val.i_int = i_width;
296     var_Set( p_vout, "vout-snapshot-width", val );
297     val.i_int = i_height;
298     var_Set( p_vout, "vout-snapshot-height", val );
299     val.i_int = i_datasize;
300     var_Set( p_vout, "vout-snapshot-datasize", val );
301
302     val.i_int = p_vout->p_sys->i_size;
303     var_Set( p_vout, "vout-snapshot-cache-size", val );
304
305     val.p_address = p_vout->p_sys->p_list;
306     var_Set( p_vout, "vout-snapshot-list-pointer", val );
307
308     /* Get the p_input pointer (to access video times) */
309     p_vout->p_sys->p_input = vlc_object_find( p_vout, VLC_OBJECT_INPUT,
310                                               FIND_PARENT );
311
312     if( !p_vout->p_sys->p_input )
313         return VLC_ENOOBJ;
314
315     if( var_Create( p_vout->p_sys->p_input, "vout-snapshot-id", VLC_VAR_INTEGER ) )
316     {
317         msg_Err( p_vout, "Cannot create vout-snapshot-id variable in p_input(%p).",
318                  p_vout->p_sys->p_input );
319         return VLC_EGENERIC;
320     }
321
322     /* Register the snapshot vout module at the input level */
323     val.p_address = p_vout;
324
325     if( var_Set( p_vout->p_sys->p_input, "vout-snapshot-id", val ) )
326     {
327         msg_Err( p_vout, "Cannot register vout-snapshot-id in p_input(%p).",
328                  p_vout->p_sys->p_input );
329         return VLC_EGENERIC;
330     }
331
332     return VLC_SUCCESS;
333 }
334
335 /*****************************************************************************
336  * End: terminate video thread output method
337  *****************************************************************************/
338 static void End( vout_thread_t *p_vout )
339 {
340     (void)p_vout;
341 }
342
343 /*****************************************************************************
344  * Destroy: destroy video thread
345  *****************************************************************************
346  * Terminate an output method created by Create
347  *****************************************************************************/
348 static void Destroy( vlc_object_t *p_this )
349 {
350     vout_thread_t *p_vout = ( vout_thread_t * )p_this;
351     int i_index;
352
353     var_Destroy( p_vout->p_sys->p_input, "vout-snapshot-id" );
354
355     vlc_object_release( p_vout->p_sys->p_input );
356     var_Destroy( p_this, "vout-snapshot-width" );
357     var_Destroy( p_this, "vout-snapshot-height" );
358     var_Destroy( p_this, "vout-snapshot-datasize" );
359
360     for( i_index = 0 ; i_index < p_vout->p_sys->i_size ; i_index++ )
361     {
362         free( p_vout->p_sys->p_list[ i_index ]->p_data );
363     }
364     free( p_vout->p_sys->p_list );
365     /* Destroy structure */
366     free( p_vout->p_sys );
367 }
368
369 /* Return the position in ms from the start of the movie */
370 static mtime_t snapshot_GetMovietime( vout_thread_t *p_vout )
371 {
372     input_thread_t *p_input = p_vout->p_sys->p_input;
373     if( !p_input )
374         return 0;
375
376     return var_GetTime( p_input, "time" ) / 1000;
377 }
378
379 /*****************************************************************************
380  * Display: displays previously rendered output
381  *****************************************************************************
382  * This function copies the rendered picture into our circular buffer.
383  *****************************************************************************/
384 static void Display( vout_thread_t *p_vout, picture_t *p_pic )
385 {
386     int i_index;
387     mtime_t i_date;
388
389     i_index = p_vout->p_sys->i_index;
390
391     vlc_memcpy( p_vout->p_sys->p_list[i_index]->p_data, p_pic->p->p_pixels,
392                 p_vout->p_sys->i_datasize );
393
394     i_date = snapshot_GetMovietime( p_vout );
395
396     p_vout->p_sys->p_list[i_index]->date = i_date;
397
398     i_index++;
399
400     if( i_index >= p_vout->p_sys->i_size )
401     {
402         i_index = 0;
403     }
404
405     p_vout->p_sys->i_index = i_index;
406 }
407