Filter SDK/C API

The header, avisynth_c.h, declares all the structures and miscellaneous constants that you might need when writing a plugin. All external plugins should #include it:

#include "avisynth_c.h"

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differences C and C++

put somewhere else.

Structures

See C++ API for descriptions. If there is no C++ API equivalent, the description is given here.

C++ API	C API
AvisynthError	?
doesn't exist	AVS_FilterInfo
VideoFrameBuffer	AVS_VideoFrameBuffer
VideoFrame	AVS_VideoFrame
AlignPlanar	doesn't exist
FillBorder	doesn't exist
ConvertAudio	doesn't exist
IScriptEnvironment	AVS_ScriptEnvironment
IClip	AVS_Clip
AVSValue	AVS_Value

AVS_FilterInfo is a structure with members (the first three are structures too):

• AVS_Clip (no members)
• AVS_ScriptEnvironment (no members)
• AVS_VideoFrame
• get_parity
• get_audio
• set_cache_hints
• free_filter
• error
• user_data

AVS_VideoFrame is a structure with members:

• offset, pitch, row_size, height, offsetU, offsetV, pitchUV
• row_sizeUV, heightUV

AVS_VideoInfo is a structure with members:

• width, height
• fps_numerator, fps_denominator
• num_frames
• pixel_type
• audio_samples_per_second
• sample_type
• num_audio_samples
• nchannels
• image_type

AVS_Value is a structure with members:

• type // 'a'rray, 'c'lip, 'b'ool, 'i'nt, 'f'loat, 's'tring, 'v'oid, or 'l'ong

              // for some function e'rror

• array_size;

 union {
   void * clip; // do not use directly, use avs_take_clip
   char boolean;
   int integer;
   float floating_pt;
   const char * string;
   const AVS_Value * array;
 } d;

Constants

The available constants are the sames ones as in the C++ API.

Note contrary to the C++ API, float audio is not typedef'd to SFLOAT.

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source: http://forum.doom9.org/showthread.php?p=1464911#post1464911

compiling plugins: http://forum.doom9.org/showthread.php?p=1092380#post1092380

example: http://forum.doom9.org/showthread.php?p=1001260#post1001260

For now the api is described here: http://www.kevina.org/avisynth_c/api.html . An example is given here: http://www.kevina.org/avisynth_c/example.html .