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avisynth_c.h
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1 // Avisynth C Interface Version 0.20
2 // Copyright 2003 Kevin Atkinson
3 
4 // This program is free software; you can redistribute it and/or modify
5 // it under the terms of the GNU General Public License as published by
6 // the Free Software Foundation; either version 2 of the License, or
7 // (at your option) any later version.
8 //
9 // This program is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 // GNU General Public License for more details.
13 //
14 // You should have received a copy of the GNU General Public License
15 // along with this program; if not, write to the Free Software
16 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA, or visit
17 // http://www.gnu.org/copyleft/gpl.html .
18 //
19 // As a special exception, I give you permission to link to the
20 // Avisynth C interface with independent modules that communicate with
21 // the Avisynth C interface solely through the interfaces defined in
22 // avisynth_c.h, regardless of the license terms of these independent
23 // modules, and to copy and distribute the resulting combined work
24 // under terms of your choice, provided that every copy of the
25 // combined work is accompanied by a complete copy of the source code
26 // of the Avisynth C interface and Avisynth itself (with the version
27 // used to produce the combined work), being distributed under the
28 // terms of the GNU General Public License plus this exception. An
29 // independent module is a module which is not derived from or based
30 // on Avisynth C Interface, such as 3rd-party filters, import and
31 // export plugins, or graphical user interfaces.
32 
33 // NOTE: this is a partial update of the Avisynth C interface to recognize
34 // new color spaces added in Avisynth 2.60. By no means is this document
35 // completely Avisynth 2.60 compliant.
36 
37 #ifndef __AVISYNTH_C__
38 #define __AVISYNTH_C__
39 
40 #ifdef __cplusplus
41 # define EXTERN_C extern "C"
42 #else
43 # define EXTERN_C
44 #endif
45 
46 #define AVSC_USE_STDCALL 1
47 
48 #ifndef AVSC_USE_STDCALL
49 # define AVSC_CC __cdecl
50 #else
51 # define AVSC_CC __stdcall
52 #endif
53 
54 #define AVSC_INLINE static __inline
55 
56 #ifdef AVISYNTH_C_EXPORTS
57 # define AVSC_EXPORT EXTERN_C
58 # define AVSC_API(ret, name) EXTERN_C __declspec(dllexport) ret AVSC_CC name
59 #else
60 # define AVSC_EXPORT EXTERN_C __declspec(dllexport)
61 # ifndef AVSC_NO_DECLSPEC
62 # define AVSC_API(ret, name) EXTERN_C __declspec(dllimport) ret AVSC_CC name
63 # else
64 # define AVSC_API(ret, name) typedef ret (AVSC_CC *name##_func)
65 # endif
66 #endif
67 
68 typedef unsigned char BYTE;
69 #ifdef __GNUC__
70 typedef long long int INT64;
71 #else
72 typedef __int64 INT64;
73 #endif
74 
75 
76 /////////////////////////////////////////////////////////////////////
77 //
78 // Constants
79 //
80 
81 #ifndef __AVISYNTH_H__
83 #endif
84 
85 enum {AVS_SAMPLE_INT8 = 1<<0,
90 
91 enum {AVS_PLANAR_Y=1<<0,
106 
107  // Colorspace properties.
108 enum {AVS_CS_BGR = 1<<28,
109  AVS_CS_YUV = 1<<29,
111  AVS_CS_PLANAR = 1<<31,
112 
116 
119  AVS_CS_SUB_WIDTH_2 = 0 << AVS_CS_SHIFT_SUB_WIDTH, // YV12, I420, YV16
121 
122  AVS_CS_VPLANEFIRST = 1 << 3, // YV12, YV16, YV24, YV411, YUV9
123  AVS_CS_UPLANEFIRST = 1 << 4, // I420
124 
126  AVS_CS_SUB_HEIGHT_1 = 3 << AVS_CS_SHIFT_SUB_HEIGHT, // YV16, YV24, YV411
129 
134 
137 
138  // Specific colorformats
139 enum {
144  // AVS_CS_YV12 = 1<<3 Reserved
145  // AVS_CS_I420 = 1<<4 Reserved
147 
156 };
157 
158 enum {
159  AVS_IT_BFF = 1<<0,
160  AVS_IT_TFF = 1<<1,
162 
163 enum {
174 
175 enum { //SUBTYPES
180 
181 enum {
188  };
189 
190 #define AVS_FRAME_ALIGN 16
191 
192 typedef struct AVS_Clip AVS_Clip;
194 
195 /////////////////////////////////////////////////////////////////////
196 //
197 // AVS_VideoInfo
198 //
199 
200 // AVS_VideoInfo is layed out identicly to VideoInfo
201 typedef struct AVS_VideoInfo {
202  int width, height; // width=0 means no video
205 
207 
208  int audio_samples_per_second; // 0 means no audio
212 
213  // Imagetype properties
214 
216 } AVS_VideoInfo;
217 
218 // useful functions of the above
220  { return (p->width!=0); }
221 
223  { return (p->audio_samples_per_second!=0); }
224 
226  { return !!(p->pixel_type&AVS_CS_BGR); }
227 
229  { return (p->pixel_type&AVS_CS_BGR24)==AVS_CS_BGR24; } // Clear out additional properties
230 
232  { return (p->pixel_type & AVS_CS_BGR32) == AVS_CS_BGR32 ; }
233 
235  { return !!(p->pixel_type&AVS_CS_YUV ); }
236 
238  { return (p->pixel_type & AVS_CS_YUY2) == AVS_CS_YUY2; }
239 
242 
245 
248 
251 
254 
255 AVSC_INLINE int avs_is_property(const AVS_VideoInfo * p, int property)
256  { return ((p->pixel_type & property)==property ); }
257 
259  { return !!(p->pixel_type & AVS_CS_PLANAR); }
260 
261 AVSC_INLINE int avs_is_color_space(const AVS_VideoInfo * p, int c_space)
262  { return avs_is_planar(p) ? ((p->pixel_type & AVS_CS_PLANAR_MASK) == (c_space & AVS_CS_PLANAR_FILTER)) : ((p->pixel_type & c_space) == c_space); }
263 
265  { return !!(p->image_type & AVS_IT_FIELDBASED); }
266 
268  { return ((p->image_type & AVS_IT_FIELDBASED)&&(p->image_type & (AVS_IT_BFF | AVS_IT_TFF))); }
269 
271  { return !!(p->image_type & AVS_IT_BFF); }
272 
274  { return !!(p->image_type & AVS_IT_TFF); }
275 
277 {
278  switch (p->pixel_type) {
279  case AVS_CS_BGR24: return 24;
280  case AVS_CS_BGR32: return 32;
281  case AVS_CS_YUY2: return 16;
282  case AVS_CS_YV12:
283  case AVS_CS_I420: return 12;
284  default: return 0;
285  }
286 }
288  { return pixels * (avs_bits_per_pixel(p)>>3); } // Will work on planar images, but will return only luma planes
289 
291  { return avs_bytes_from_pixels(p,p->width); } // Also only returns first plane on planar images
292 
294  { if (avs_is_planar(vi)) {int p = vi->height * ((avs_row_size(vi)+3) & ~3); p+=p>>1; return p; } return vi->height * ((avs_row_size(vi)+3) & ~3); }
295 
297  { return p->audio_samples_per_second; }
298 
299 
301 {
302  switch (p->sample_type) {
303  case AVS_SAMPLE_INT8: return sizeof(signed char);
304  case AVS_SAMPLE_INT16: return sizeof(signed short);
305  case AVS_SAMPLE_INT24: return 3;
306  case AVS_SAMPLE_INT32: return sizeof(signed int);
307  case AVS_SAMPLE_FLOAT: return sizeof(float);
308  default: return 0;
309  }
310 }
312  { return p->nchannels*avs_bytes_per_channel_sample(p);}
313 
315  { return ((INT64)(frames) * p->audio_samples_per_second * p->fps_denominator / p->fps_numerator); }
316 
318  { return (int)(samples * (INT64)p->fps_numerator / (INT64)p->fps_denominator / (INT64)p->audio_samples_per_second); }
319 
321  { return bytes / avs_bytes_per_audio_sample(p); }
322 
324  { return samples * avs_bytes_per_audio_sample(p); }
325 
327  { return p->nchannels; }
328 
330  { return p->sample_type;}
331 
332 // useful mutator
334  { p->image_type|=property; }
335 
337  { p->image_type&=~property; }
338 
339 AVSC_INLINE void avs_set_field_based(AVS_VideoInfo * p, int isfieldbased)
340  { if (isfieldbased) p->image_type|=AVS_IT_FIELDBASED; else p->image_type&=~AVS_IT_FIELDBASED; }
341 
342 AVSC_INLINE void avs_set_fps(AVS_VideoInfo * p, unsigned numerator, unsigned denominator)
343 {
344  unsigned x=numerator, y=denominator;
345  while (y) { // find gcd
346  unsigned t = x%y; x = y; y = t;
347  }
348  p->fps_numerator = numerator/x;
349  p->fps_denominator = denominator/x;
350 }
351 
353 {
354  return (x->pixel_type == y->pixel_type)
355  || (avs_is_yv12(x) && avs_is_yv12(y));
356 }
357 
358 /////////////////////////////////////////////////////////////////////
359 //
360 // AVS_VideoFrame
361 //
362 
363 // VideoFrameBuffer holds information about a memory block which is used
364 // for video data. For efficiency, instances of this class are not deleted
365 // when the refcount reaches zero; instead they're stored in a linked list
366 // to be reused. The instances are deleted when the corresponding AVS
367 // file is closed.
368 
369 // AVS_VideoFrameBuffer is layed out identicly to VideoFrameBuffer
370 // DO NOT USE THIS STRUCTURE DIRECTLY
371 typedef struct AVS_VideoFrameBuffer {
374  // sequence_number is incremented every time the buffer is changed, so
375  // that stale views can tell they're no longer valid.
376  volatile long sequence_number;
377 
378  volatile long refcount;
380 
381 // VideoFrame holds a "window" into a VideoFrameBuffer.
382 
383 // AVS_VideoFrame is layed out identicly to IVideoFrame
384 // DO NOT USE THIS STRUCTURE DIRECTLY
385 typedef struct AVS_VideoFrame {
386  volatile long refcount;
388  int offset, pitch, row_size, height, offsetU, offsetV, pitchUV; // U&V offsets are from top of picture.
391 
392 // Access functions for AVS_VideoFrame
394  return p->pitch;}
395 
396 AVSC_INLINE int avs_get_pitch_p(const AVS_VideoFrame * p, int plane) {
397  switch (plane) {
398  case AVS_PLANAR_U: case AVS_PLANAR_V: return p->pitchUV;}
399  return p->pitch;}
400 
402  return p->row_size; }
403 
404 AVSC_INLINE int avs_get_row_size_p(const AVS_VideoFrame * p, int plane) {
405  int r;
406  switch (plane) {
407  case AVS_PLANAR_U: case AVS_PLANAR_V:
408  if (p->pitchUV) return p->row_sizeUV;
409  else return 0;
411  if (p->pitchUV) {
412  r = (p->row_sizeUV+AVS_FRAME_ALIGN-1)&(~(AVS_FRAME_ALIGN-1)); // Aligned rowsize
413  if (r < p->pitchUV)
414  return r;
415  return p->row_sizeUV;
416  } else return 0;
418  r = (p->row_size+AVS_FRAME_ALIGN-1)&(~(AVS_FRAME_ALIGN-1)); // Aligned rowsize
419  if (r <= p->pitch)
420  return r;
421  return p->row_size;
422  }
423  return p->row_size;
424 }
425 
427  return p->height;}
428 
429 AVSC_INLINE int avs_get_height_p(const AVS_VideoFrame * p, int plane) {
430  switch (plane) {
431  case AVS_PLANAR_U: case AVS_PLANAR_V:
432  if (p->pitchUV) return p->heightUV;
433  return 0;
434  }
435  return p->height;}
436 
438  return p->vfb->data + p->offset;}
439 
440 AVSC_INLINE const BYTE* avs_get_read_ptr_p(const AVS_VideoFrame * p, int plane)
441 {
442  switch (plane) {
443  case AVS_PLANAR_U: return p->vfb->data + p->offsetU;
444  case AVS_PLANAR_V: return p->vfb->data + p->offsetV;
445  default: return p->vfb->data + p->offset;}
446 }
447 
449  return (p->refcount == 1 && p->vfb->refcount == 1);}
450 
452 {
453  if (avs_is_writable(p)) {
454  ++p->vfb->sequence_number;
455  return p->vfb->data + p->offset;
456  } else
457  return 0;
458 }
459 
461 {
462  if (plane==AVS_PLANAR_Y && avs_is_writable(p)) {
463  ++p->vfb->sequence_number;
464  return p->vfb->data + p->offset;
465  } else if (plane==AVS_PLANAR_Y) {
466  return 0;
467  } else {
468  switch (plane) {
469  case AVS_PLANAR_U: return p->vfb->data + p->offsetU;
470  case AVS_PLANAR_V: return p->vfb->data + p->offsetV;
471  default: return p->vfb->data + p->offset;
472  }
473  }
474 }
475 
476 
477 AVSC_API(void, avs_release_video_frame)(AVS_VideoFrame *);
478 // makes a shallow copy of a video frame
479 AVSC_API(AVS_VideoFrame *, avs_copy_video_frame)(AVS_VideoFrame *);
480 
481 #ifndef AVSC_NO_DECLSPEC
483  {avs_release_video_frame(f);}
485  {return avs_copy_video_frame(f);}
486 #endif
487 
488 /////////////////////////////////////////////////////////////////////
489 //
490 // AVS_Value
491 //
492 
493 // Treat AVS_Value as a fat pointer. That is use avs_copy_value
494 // and avs_release_value appropiaty as you would if AVS_Value was
495 // a pointer.
496 
497 // To maintain source code compatibility with future versions of the
498 // avisynth_c API don't use the AVS_Value directly. Use the helper
499 // functions below.
500 
501 // AVS_Value is layed out identicly to AVSValue
502 typedef struct AVS_Value AVS_Value;
503 struct AVS_Value {
504  short type; // 'a'rray, 'c'lip, 'b'ool, 'i'nt, 'f'loat, 's'tring, 'v'oid, or 'l'ong
505  // for some function e'rror
506  short array_size;
507  union {
508  void * clip; // do not use directly, use avs_take_clip
509  char boolean;
510  int integer;
511  float floating_pt;
512  const char * string;
513  const AVS_Value * array;
514  } d;
515 };
516 
517 // AVS_Value should be initilized with avs_void.
518 // Should also set to avs_void after the value is released
519 // with avs_copy_value. Consider it the equalvent of setting
520 // a pointer to NULL
521 static const AVS_Value avs_void = {'v'};
522 
523 AVSC_API(void, avs_copy_value)(AVS_Value * dest, AVS_Value src);
524 AVSC_API(void, avs_release_value)(AVS_Value);
525 
526 AVSC_INLINE int avs_defined(AVS_Value v) { return v.type != 'v'; }
527 AVSC_INLINE int avs_is_clip(AVS_Value v) { return v.type == 'c'; }
528 AVSC_INLINE int avs_is_bool(AVS_Value v) { return v.type == 'b'; }
529 AVSC_INLINE int avs_is_int(AVS_Value v) { return v.type == 'i'; }
530 AVSC_INLINE int avs_is_float(AVS_Value v) { return v.type == 'f' || v.type == 'i'; }
531 AVSC_INLINE int avs_is_string(AVS_Value v) { return v.type == 's'; }
532 AVSC_INLINE int avs_is_array(AVS_Value v) { return v.type == 'a'; }
533 AVSC_INLINE int avs_is_error(AVS_Value v) { return v.type == 'e'; }
534 
535 AVSC_API(AVS_Clip *, avs_take_clip)(AVS_Value, AVS_ScriptEnvironment *);
536 AVSC_API(void, avs_set_to_clip)(AVS_Value *, AVS_Clip *);
537 
539  { return v.d.boolean; }
541  { return v.d.integer; }
543  { return avs_is_error(v) || avs_is_string(v) ? v.d.string : 0; }
545  { return avs_is_int(v) ? v.d.integer : v.d.floating_pt; }
547  { return avs_is_error(v) ? v.d.string : 0; }
549  { return v.d.array; }
551  { return avs_is_array(v) ? v.array_size : 1; }
553  { return avs_is_array(v) ? v.d.array[index] : v; }
554 
555 // only use these functions on an AVS_Value that does not already have
556 // an active value. Remember, treat AVS_Value as a fat pointer.
558  { AVS_Value v; v.type = 'b'; v.d.boolean = v0 == 0 ? 0 : 1; return v; }
560  { AVS_Value v; v.type = 'i'; v.d.integer = v0; return v; }
562  { AVS_Value v; v.type = 's'; v.d.string = v0; return v; }
564  { AVS_Value v; v.type = 'f'; v.d.floating_pt = v0; return v;}
566  { AVS_Value v; v.type = 'e'; v.d.string = v0; return v; }
567 #ifndef AVSC_NO_DECLSPEC
569  { AVS_Value v; avs_set_to_clip(&v, v0); return v; }
570 #endif
572  { AVS_Value v; v.type = 'a'; v.d.array = v0; v.array_size = size; return v; }
573 
574 /////////////////////////////////////////////////////////////////////
575 //
576 // AVS_Clip
577 //
578 
579 AVSC_API(void, avs_release_clip)(AVS_Clip *);
580 AVSC_API(AVS_Clip *, avs_copy_clip)(AVS_Clip *);
581 
582 AVSC_API(const char *, avs_clip_get_error)(AVS_Clip *); // return 0 if no error
583 
584 AVSC_API(const AVS_VideoInfo *, avs_get_video_info)(AVS_Clip *);
585 
586 AVSC_API(int, avs_get_version)(AVS_Clip *);
587 
588 AVSC_API(AVS_VideoFrame *, avs_get_frame)(AVS_Clip *, int n);
589 // The returned video frame must be released with avs_release_video_frame
590 
591 AVSC_API(int, avs_get_parity)(AVS_Clip *, int n);
592 // return field parity if field_based, else parity of first field in frame
593 
594 AVSC_API(int, avs_get_audio)(AVS_Clip *, void * buf,
596 // start and count are in samples
597 
598 AVSC_API(int, avs_set_cache_hints)(AVS_Clip *,
600 
601 // This is the callback type used by avs_add_function
602 typedef AVS_Value (AVSC_CC * AVS_ApplyFunc)
604 
605 typedef struct AVS_FilterInfo AVS_FilterInfo;
607 {
608  // these members should not be modified outside of the AVS_ApplyFunc callback
614  int (AVSC_CC * get_audio)(AVS_FilterInfo *, void * buf,
616  int (AVSC_CC * set_cache_hints)(AVS_FilterInfo *, int cachehints,
617  int frame_range);
618  void (AVSC_CC * free_filter)(AVS_FilterInfo *);
619 
620  // Should be set when ever there is an error to report.
621  // It is cleared before any of the above methods are called
622  const char * error;
623  // this is to store whatever and may be modified at will
624  void * user_data;
625 };
626 
627 // Create a new filter
628 // fi is set to point to the AVS_FilterInfo so that you can
629 // modify it once it is initilized.
630 // store_child should generally be set to true. If it is not
631 // set than ALL methods (the function pointers) must be defined
632 // If it is set than you do not need to worry about freeing the child
633 // clip.
634 AVSC_API(AVS_Clip *, avs_new_c_filter)(AVS_ScriptEnvironment * e,
637 
638 /////////////////////////////////////////////////////////////////////
639 //
640 // AVS_ScriptEnvironment
641 //
642 
643 // For GetCPUFlags. These are backwards-compatible with those in VirtualDub.
644 enum {
645  /* slowest CPU to support extension */
646  AVS_CPU_FORCE = 0x01, // N/A
647  AVS_CPU_FPU = 0x02, // 386/486DX
648  AVS_CPU_MMX = 0x04, // P55C, K6, PII
649  AVS_CPU_INTEGER_SSE = 0x08, // PIII, Athlon
650  AVS_CPU_SSE = 0x10, // PIII, Athlon XP/MP
651  AVS_CPU_SSE2 = 0x20, // PIV, Hammer
652  AVS_CPU_3DNOW = 0x40, // K6-2
653  AVS_CPU_3DNOW_EXT = 0x80, // Athlon
654  AVS_CPU_X86_64 = 0xA0, // Hammer (note: equiv. to 3DNow + SSE2,
655  // which only Hammer will have anyway)
656  AVS_CPUF_SSE3 = 0x100, // PIV+, K8 Venice
657  AVS_CPUF_SSSE3 = 0x200, // Core 2
658  AVS_CPUF_SSE4 = 0x400, // Penryn, Wolfdale, Yorkfield
660  AVS_CPUF_SSE4_2 = 0x800, // Nehalem
661 };
662 
663 AVSC_API(const char *, avs_get_error)(AVS_ScriptEnvironment *); // return 0 if no error
664 
665 AVSC_API(long, avs_get_cpu_flags)(AVS_ScriptEnvironment *);
666 AVSC_API(int, avs_check_version)(AVS_ScriptEnvironment *, int version);
667 
668 AVSC_API(char *, avs_save_string)(AVS_ScriptEnvironment *, const char* s, int length);
669 AVSC_API(char *, avs_sprintf)(AVS_ScriptEnvironment *, const char * fmt, ...);
670 
671 AVSC_API(char *, avs_vsprintf)(AVS_ScriptEnvironment *, const char * fmt, void* val);
672  // note: val is really a va_list; I hope everyone typedefs va_list to a pointer
673 
674 AVSC_API(int, avs_add_function)(AVS_ScriptEnvironment *,
675  const char * name, const char * params,
676  AVS_ApplyFunc apply, void * user_data);
677 
678 AVSC_API(int, avs_function_exists)(AVS_ScriptEnvironment *, const char * name);
679 
680 AVSC_API(AVS_Value, avs_invoke)(AVS_ScriptEnvironment *, const char * name,
681  AVS_Value args, const char** arg_names);
682 // The returned value must be be released with avs_release_value
683 
684 AVSC_API(AVS_Value, avs_get_var)(AVS_ScriptEnvironment *, const char* name);
685 // The returned value must be be released with avs_release_value
686 
687 AVSC_API(int, avs_set_var)(AVS_ScriptEnvironment *, const char* name, AVS_Value val);
688 
689 AVSC_API(int, avs_set_global_var)(AVS_ScriptEnvironment *, const char* name, const AVS_Value val);
690 
691 //void avs_push_context(AVS_ScriptEnvironment *, int level=0);
692 //void avs_pop_context(AVS_ScriptEnvironment *);
693 
694 AVSC_API(AVS_VideoFrame *, avs_new_video_frame_a)(AVS_ScriptEnvironment *,
695  const AVS_VideoInfo * vi, int align);
696 // align should be at least 16
697 
698 #ifndef AVSC_NO_DECLSPEC
701  const AVS_VideoInfo * vi)
702  {return avs_new_video_frame_a(env,vi,AVS_FRAME_ALIGN);}
703 
706  const AVS_VideoInfo * vi)
707  {return avs_new_video_frame_a(env,vi,AVS_FRAME_ALIGN);}
708 #endif
709 
710 
711 AVSC_API(int, avs_make_writable)(AVS_ScriptEnvironment *, AVS_VideoFrame * * pvf);
712 
713 AVSC_API(void, avs_bit_blt)(AVS_ScriptEnvironment *, BYTE* dstp, int dst_pitch, const BYTE* srcp, int src_pitch, int row_size, int height);
714 
716 AVSC_API(void, avs_at_exit)(AVS_ScriptEnvironment *, AVS_ShutdownFunc function, void * user_data);
717 
719 // The returned video frame must be be released
720 
721 AVSC_API(int, avs_set_memory_max)(AVS_ScriptEnvironment *, int mem);
722 
723 AVSC_API(int, avs_set_working_dir)(AVS_ScriptEnvironment *, const char * newdir);
724 
725 // avisynth.dll exports this; it's a way to use it as a library, without
726 // writing an AVS script or without going through AVIFile.
727 AVSC_API(AVS_ScriptEnvironment *, avs_create_script_environment)(int version);
728 
729 // this symbol is the entry point for the plugin and must
730 // be defined
733 
734 
735 AVSC_API(void, avs_delete_script_environment)(AVS_ScriptEnvironment *);
736 
737 
739 // The returned video frame must be be released
740 
741 #ifdef AVSC_NO_DECLSPEC
742 // use LoadLibrary and related functions to dynamically load Avisynth instead of declspec(dllimport)
743 /*
744  The following functions needs to have been declared, probably from windows.h
745 
746  void* malloc(size_t)
747  void free(void*);
748 
749  HMODULE LoadLibrary(const char*);
750  void* GetProcAddress(HMODULE, const char*);
751  FreeLibrary(HMODULE);
752 */
753 
754 
755 typedef struct AVS_Library AVS_Library;
756 
757 #define AVSC_DECLARE_FUNC(name) name##_func name
758 
759 struct AVS_Library {
760  HMODULE handle;
761 
762  AVSC_DECLARE_FUNC(avs_add_function);
763  AVSC_DECLARE_FUNC(avs_at_exit);
764  AVSC_DECLARE_FUNC(avs_bit_blt);
765  AVSC_DECLARE_FUNC(avs_check_version);
766  AVSC_DECLARE_FUNC(avs_clip_get_error);
767  AVSC_DECLARE_FUNC(avs_copy_clip);
768  AVSC_DECLARE_FUNC(avs_copy_value);
769  AVSC_DECLARE_FUNC(avs_copy_video_frame);
770  AVSC_DECLARE_FUNC(avs_create_script_environment);
771  AVSC_DECLARE_FUNC(avs_delete_script_environment);
772  AVSC_DECLARE_FUNC(avs_function_exists);
773  AVSC_DECLARE_FUNC(avs_get_audio);
774  AVSC_DECLARE_FUNC(avs_get_cpu_flags);
775  AVSC_DECLARE_FUNC(avs_get_error);
776  AVSC_DECLARE_FUNC(avs_get_frame);
777  AVSC_DECLARE_FUNC(avs_get_parity);
778  AVSC_DECLARE_FUNC(avs_get_var);
779  AVSC_DECLARE_FUNC(avs_get_version);
780  AVSC_DECLARE_FUNC(avs_get_video_info);
781  AVSC_DECLARE_FUNC(avs_invoke);
782  AVSC_DECLARE_FUNC(avs_make_writable);
783  AVSC_DECLARE_FUNC(avs_new_c_filter);
784  AVSC_DECLARE_FUNC(avs_new_video_frame_a);
785  AVSC_DECLARE_FUNC(avs_release_clip);
786  AVSC_DECLARE_FUNC(avs_release_value);
787  AVSC_DECLARE_FUNC(avs_release_video_frame);
788  AVSC_DECLARE_FUNC(avs_save_string);
789  AVSC_DECLARE_FUNC(avs_set_cache_hints);
790  AVSC_DECLARE_FUNC(avs_set_global_var);
791  AVSC_DECLARE_FUNC(avs_set_memory_max);
792  AVSC_DECLARE_FUNC(avs_set_to_clip);
793  AVSC_DECLARE_FUNC(avs_set_var);
794  AVSC_DECLARE_FUNC(avs_set_working_dir);
795  AVSC_DECLARE_FUNC(avs_sprintf);
796  AVSC_DECLARE_FUNC(avs_subframe);
797  AVSC_DECLARE_FUNC(avs_subframe_planar);
798  AVSC_DECLARE_FUNC(avs_take_clip);
799  AVSC_DECLARE_FUNC(avs_vsprintf);
800 };
801 
802 #undef AVSC_DECLARE_FUNC
803 
804 
805 AVSC_INLINE AVS_Library * avs_load_library() {
806  AVS_Library *library = (AVS_Library *)malloc(sizeof(AVS_Library));
807  if (library == NULL)
808  return NULL;
809  library->handle = LoadLibrary("avisynth");
810  if (library->handle == NULL)
811  goto fail;
812 
813 #define __AVSC_STRINGIFY(x) #x
814 #define AVSC_STRINGIFY(x) __AVSC_STRINGIFY(x)
815 #define AVSC_LOAD_FUNC(name) {\
816  library->name = (name##_func) GetProcAddress(library->handle, AVSC_STRINGIFY(name));\
817  if (library->name == NULL)\
818  goto fail;\
819 }
820 
821  AVSC_LOAD_FUNC(avs_add_function);
822  AVSC_LOAD_FUNC(avs_at_exit);
823  AVSC_LOAD_FUNC(avs_bit_blt);
824  AVSC_LOAD_FUNC(avs_check_version);
825  AVSC_LOAD_FUNC(avs_clip_get_error);
826  AVSC_LOAD_FUNC(avs_copy_clip);
827  AVSC_LOAD_FUNC(avs_copy_value);
828  AVSC_LOAD_FUNC(avs_copy_video_frame);
829  AVSC_LOAD_FUNC(avs_create_script_environment);
830  AVSC_LOAD_FUNC(avs_delete_script_environment);
831  AVSC_LOAD_FUNC(avs_function_exists);
832  AVSC_LOAD_FUNC(avs_get_audio);
833  AVSC_LOAD_FUNC(avs_get_cpu_flags);
834  AVSC_LOAD_FUNC(avs_get_error);
835  AVSC_LOAD_FUNC(avs_get_frame);
836  AVSC_LOAD_FUNC(avs_get_parity);
837  AVSC_LOAD_FUNC(avs_get_var);
838  AVSC_LOAD_FUNC(avs_get_version);
839  AVSC_LOAD_FUNC(avs_get_video_info);
840  AVSC_LOAD_FUNC(avs_invoke);
841  AVSC_LOAD_FUNC(avs_make_writable);
842  AVSC_LOAD_FUNC(avs_new_c_filter);
843  AVSC_LOAD_FUNC(avs_new_video_frame_a);
844  AVSC_LOAD_FUNC(avs_release_clip);
845  AVSC_LOAD_FUNC(avs_release_value);
846  AVSC_LOAD_FUNC(avs_release_video_frame);
847  AVSC_LOAD_FUNC(avs_save_string);
848  AVSC_LOAD_FUNC(avs_set_cache_hints);
849  AVSC_LOAD_FUNC(avs_set_global_var);
850  AVSC_LOAD_FUNC(avs_set_memory_max);
851  AVSC_LOAD_FUNC(avs_set_to_clip);
852  AVSC_LOAD_FUNC(avs_set_var);
853  AVSC_LOAD_FUNC(avs_set_working_dir);
854  AVSC_LOAD_FUNC(avs_sprintf);
855  AVSC_LOAD_FUNC(avs_subframe);
856  AVSC_LOAD_FUNC(avs_subframe_planar);
857  AVSC_LOAD_FUNC(avs_take_clip);
858  AVSC_LOAD_FUNC(avs_vsprintf);
859 
860 #undef __AVSC_STRINGIFY
861 #undef AVSC_STRINGIFY
862 #undef AVSC_LOAD_FUNC
863 
864  return library;
865 
866 fail:
867  free(library);
868  return NULL;
869 }
870 
871 AVSC_INLINE void avs_free_library(AVS_Library *library) {
872  if (library == NULL)
873  return;
874  FreeLibrary(library->handle);
875  free(library);
876 }
877 #endif
878 
879 #endif