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2013-05-09T21:33:53Z

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92.233.37.17: /* Video-related information */

2011-07-29T13:06:16Z

‎Video-related information

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VideoInfo provides basic information about the clip your filter receives.

== Getting information from VideoInfo ==

=== Video-related information ===

bool HasVideo();

This will return true if there is any video in the given clip.

bool IsRGB24();
bool IsRGB32();
bool IsRGB();

This will return true if the colorspace is [[RGB]] (in any way). The first two return true if the clip has the specific RGB colorspace ([[RGB24]] and [[RGB32]]). The third returns true for any RGB colorspace; future formats could also apply.

bool IsYUY2();
bool IsYV12();
bool IsYUV();

This will return true if the colorspace is [[YUV]] (in any way). The first two return true if the clip has the specific YUV colorspace ([[YUY2]] and [[YV12]]). The third returns true for any YUV colorspace; future formats could also apply. Note that I420 is also reported as YV12, because planes are automatically swapped.

bool IsColorSpace(int c_space);

This function will check if the colorspace (VideoInfo.pixel_type) is the same as given c_space (or more general it checks for a [[Colorspace property]] (see avisynth.h)).

bool IsSameColorspace(const VideoInfo& vi2);

This function will compare two VideoInfos, and check if the colorspace is the same. Note: It does not check imagesize or similar properties.

bool Is(int property);

This function is reserved for future use. Currently works as IsColorSpace.

bool IsPlanar();

This will return true if the video is planar. For now only YV12 returns true, but future formats might also do so. See the [[Planar]] image format.

bool IsFieldBased();

This will return true if the video has been through a [[SeparateFields]], and the video has not been [[Weave|weaved]] yet. Otherwise it will return false.

bool IsParityKnown();

This will return true if the video parity is known.

bool IsBFF();
bool IsTFF();

This will return true if the video is bottom-field-first or top-field-first respectively.

void SetFieldBased(bool isfieldbased);

This will set the field-based property to true (respectively false) if isfieldbased=true (respectively false).

void Set(int property);
void Clear(int property);

This sets respectively clears an image_type property like: IT_BFF, IT_TFF or IT_FIELDBASED. See field.h for examples.

int BitsPerPixel();

This will return the number of bits per pixel. This can be:

{| border="1" cellpadding="4"
!width=50%| pixel_type
!width=50%| nr of bits
|-
| CS_BGR24
| 24
|-
| CS_BGR32
| 32
|-
| CS_YUY2
| 16
|-
| CS_YV12, CS_I420
| 12
|}

void SetFPS(unsigned numerator, unsigned denominator);

This will set the framerate.

void MulDivFPS(unsigned multiplier, unsigned divisor);

This will multiply the denominator by ''multiplier'' and scale the numerator and modified denominator.

There is some other useful information in VideoInfo structure (width, height, fps_numerator, fps_denominator, num_frames, pixel_type and image_type). See 'avisynth.h' header file.

=== Audio-related information ===

bool HasAudio();

This will return true if there is any audio in the given clip.

int AudioChannels();

This will return the number of audio channels.

int SampleType();

This will return the sampletype. This can be:

{| border="1" cellpadding="4"
!width=50%| pixel_type
!width=50%| nr of bits
|-
| SAMPLE_INT8
| 1<<0
|-
| SAMPLE_INT16
| 1<<1
|-
| SAMPLE_INT24
| 1<<2
|-
| SAMPLE_INT32
| 1<<3
|-
| SAMPLE_FLOAT
| 1<<4
|}

bool IsSampleType(int testtype);

This function will check if the sampletype (VideoInfo.sample_type) is the same as testtype.

int SamplesPerSecond();

This will return the number of bytes per second.

int BytesPerAudioSample();

This will return the number of bytes per sample:

int BytesPerChannelSample()

This will return the number of bytes per channel-sample. This can be:

{| border="1" cellpadding="4"
!width=50%| sample
!width=50%| nr of bytes
|-
| SAMPLE_INT8
| sizeof(signed char)
|-
| SAMPLE_INT16
| sizeof(signed short)
|-
| SAMPLE_INT24
| 3
|-
| SAMPLE_INT32
| sizeof(signed int)
|-
| SAMPLE_FLOAT
| sizeof(SFLOAT)
|}

__int64 AudioSamplesFromFrames(__int64 frames);

This returns the number of audiosamples from the first ''frames'' frames.

int FramesFromAudioSamples(__int64 samples);

This returns the number of frames from the first ''samples'' audiosamples.

__int64 AudioSamplesFromBytes(__int64 bytes);

This returns the number of audiosamples from the first ''bytes'' bytes.

__int64 BytesFromAudioSamples(__int64 samples);

This returns the number of bytes from the first ''samples'' audiosamples.

There is some other useful information in VideoInfo structure (audio_samples_per_second, sample_type, num_audio_samples and nchannels). See 'avisynth.h' header file.

Back to [[Filter_SDK/Internal_functions|Internal functions]].

[[Category:FilterSDK]]

Filter SDK/VideoInfo - Revision history

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92.233.37.17: /* Video-related information */