ResampleAudio - Revision history

Reel.Deal: add link to avs+ documentation

2022-09-18T04:39:09Z

add link to avs+ documentation

← Older revision		Revision as of 06:39, 18 September 2022
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	<div style="max-width:62em" >		<div style="max-width:62em" >
			<div {{BlueBox2\|40\|0\|3px solid purple}} >
			{{AvsPlusFullname}}<br>
			Up-to-date documentation: [https://avisynthplus.readthedocs.io/en/latest/avisynthdoc/corefilters/resampleaudio.html https://avisynthplus.readthedocs.io]
			</div>


	High-quality change of audio sample rate.		High-quality change of audio sample rate.
	* Accepts any number of channels.		* Accepts any number of channels.

Raffriff42: spellcheck

2016-02-27T18:10:13Z

spellcheck

← Older revision		Revision as of 20:10, 27 February 2016
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	* The conversion is skipped if the sample rate is already at the given rate.		* The conversion is skipped if the sample rate is already at the given rate.
	* Supports ''fractional'' resampling (where {{FuncArg\|new_rate_denominator}} ≠ 1).		* Supports ''fractional'' resampling (where {{FuncArg\|new_rate_denominator}} ≠ 1).
	* Note, internal rounding may affect [[Clip_properties\|AudioDuration]] ~~slighly~~ – see [[#Examples\|example]] below.		* Note, internal rounding may affect [[Clip_properties\|AudioDuration]] slightly – see [[#Examples\|example]] below.
	</div>		</div>

Raffriff42: one more touch-up

2016-02-27T14:13:00Z

one more touch-up

← Older revision		Revision as of 16:13, 27 February 2016
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	\|ResampleAudio(clip ''clip'', ''int new_rate_numerator'' [, int ''new_rate_denominator'' ] )		\|ResampleAudio(clip ''clip'', ''int new_rate_numerator'' [, int ''new_rate_denominator'' ] )
	}}		}}

			:{{Par2\|clip \|clip\|}}
			::Source clip. Supported [[ConvertAudio\|audio sample types]]: 16-bit integer and [[Float\|32-bit floating-point]].
			::Other sample types (8-, 24- and 32-bit integer) are automatically converted to floating-point.

	:{{Par2\|new_rate_numerator\|int\|}}		:{{Par2\|new_rate_numerator\|int\|}}

Raffriff42: remove unclear section on fractional resampling

2016-02-27T01:12:25Z

remove unclear section on fractional resampling

← Older revision		Revision as of 03:12, 27 February 2016
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	* Accepts any number of channels.		* Accepts any number of channels.
	* The conversion is skipped if the sample rate is already at the given rate.		* The conversion is skipped if the sample rate is already at the given rate.
	* Supports ''fractional'' resampling (where {{FuncArg\|new_rate_denominator}} != 1).		* Supports ''fractional'' resampling (where {{FuncArg\|new_rate_denominator}} ≠ 1).
			* Note, internal rounding may affect [[Clip_properties\|AudioDuration]] slighly – see [[#Examples\|example]] below.
	</div>		</div>

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	:{{Par2\|new_rate_numerator\|int\|}}		:{{Par2\|new_rate_numerator\|int\|}}
	::Set new sample rate~~, or if {{FuncArg\|new_rate_denominator}} != 1, set the numerator~~.		::Set the numerator for the new sample rate.

	:{{Par2\|new_rate_denominator\|int\|1}}		:{{Par2\|new_rate_denominator\|int\|1}}
	::Set the denominator for the new sample rate. Default 1.		::Set the denominator for the new sample rate. Default 1.


	~~When using fractional resampling (where {{FuncArg\|new_rate_denominator}} != 1) the output audio sample rate is given by :~~
	~~:int({{FuncArg\|new_rate_numerator}} / {{FuncArg\|new_rate_denominator}} + 0.5)~~

	~~However internally the resampling factor used is :~~
	~~:{{FuncArg\|new_rate_numerator}} / ({{FuncArg\|new_rate_denominator}} * [[Clip_properties\|AudioRate]])~~

	~~This causes the audio duration to vary slightly (which is generally what is desired).{{Clarify}}~~
	</div>		</div>

Raffriff42: correction in 4% speed up example

2016-02-17T08:17:06Z

correction in 4% speed up example

← Older revision		Revision as of 10:17, 17 February 2016
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	''# final sample rate:''		''# final sample rate:''
	[[AssumeSampleRate]](Ar)		[[AssumeSampleRate]](Ar)
	[[AssumeFPS]](Nfr_num, Nfr_den, ~~False~~)		[[AssumeFPS]](Nfr_num, Nfr_den, false)
	</div>		</div>
	<div style="max-width:62em" >		<div style="max-width:62em" >
	In the example above, the ''intermediate sample rate'' needs to be		In the example above, the intermediate sample rate needs to be
	:(44100 * 24000 ~~/ 1001~~) / (25 * 1) = 42293.706294		:<tt>([[Clip_properties\|AudioRate]][[Clip_properties\|FramerateNumerator]]Nfr_den=1)/([[Clip_properties\|FramerateDenominator]]*Nfr_num=25)</tt>
			:or <tt>(44100 * 24000 * 1) / (1001 * 25)</tt> = 42293.706294...
	but because audio sample rates are always integers, 42293.706294 must be rounded to 42294, <br>		but because audio sample rates are always integers, 42293.706294 must be rounded to 42294, <br>
	which results in a time slippage of about 30ms per hour.		which results in a time slippage of about 30ms per hour.
	</div>		</div>

Raffriff42: formatting, links, phrasing

2016-02-15T06:21:29Z

formatting, links, phrasing

← Older revision		Revision as of 08:21, 15 February 2016
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	{{~~Template:FuncDef~~\|~~ResampleAudio(clip, int new_rate_numerator [, int~~ new_rate_denominator])}}		<div style="max-width:62em" >
			High-quality change of audio sample rate.
			* Accepts any number of channels.
			* The conversion is skipped if the sample rate is already at the given rate.
			* Supports ''fractional'' resampling (where {{FuncArg\|new_rate_denominator}} != 1).
			</div>

	~~ResampleAudio performs a high-quality change of audio sample rate.~~
	~~The conversion is skipped if the samplerate is already at the given rate.~~

	~~When using fractional resampling the output audio samplerate is given by~~ :		== Syntax and Parameters ==
			<div style="max-width:62em" >
			{{FuncDef
			\|ResampleAudio(clip ''clip'', ''int new_rate_numerator'' [, int ''new_rate_denominator'' ] )
			}}

	int~~(new_rate_numerator /~~ new_rate_denominator ~~+ 0~~.5)		:{{Par2\|new_rate_numerator\|int\|}}
			::Set new sample rate, or if {{FuncArg\|new_rate_denominator}} != 1, set the numerator.

	~~However~~ the ~~internally~~ the ~~resampling factor used is :~~		:{{Par2\|new_rate_denominator\|int\|1}}
			::Set the denominator for the new sample rate. Default 1.

	~~new_rate_numerator / (new_rate_denominator * old_sample_rate)~~

	~~This causes~~ the audio ~~duration to vary slightly~~ (~~which is generally what is desired~~).		When using fractional resampling (where {{FuncArg\|new_rate_denominator}} != 1) the output audio sample rate is given by :
			:int({{FuncArg\|new_rate_numerator}} / {{FuncArg\|new_rate_denominator}} + 0.5)

	~~Starting from v2.53 ResampleAudio accepts any number of channels.~~		However internally the resampling factor used is :
	~~Starting from v2.56 ResampleAudio process float samples directly. Support fractional resampling.~~		:{{FuncArg\|new_rate_numerator}} / ({{FuncArg\|new_rate_denominator}} * [[Clip_properties\|AudioRate]])

	~~# Resamples~~ audio to 48 kHz:		This causes the audio duration to vary slightly (which is generally what is desired).{{Clarify}}
	source = ~~AviSource~~("c:\audio.wav")		</div>


			== Examples ==
			* Resample audio to 48 kHz:
			<div {{BoxWidthIndent\|26\|2}} >
			source = [[WavSource]]("c:\audio.wav")
	return ResampleAudio(source, 48000)		return ResampleAudio(source, 48000)
			</div>

			* Exact 4% speed up for PAL telecine:
	# Exact 4% speed up for PAL telecine:		<div {{BoxWidthIndent\|56\|2}} >
	Nfr_num = 25		Nfr_num = 25
	Nfr_den = 1		Nfr_den = 1
	AviSource("C:\Film.avi") # 23.976 fps, 44100Hz		[[AviSource]]("C:\Film.avi") # 23.976 fps, 44100Hz
	Ar = ~~Audiorate()~~		Ar = [[Clip_properties\|AudioRate]]
	ResampleAudio(ArFramerateNumerator()Nfr_den, FramerateDenominator()*Nfr_num)		''# intermediate sample rate:''
	AssumeSampleRate(Ar)		ResampleAudio(Ar[[Clip_properties\|FramerateNumerator]]Nfr_den, [[Clip_properties\|FramerateDenominator]]*Nfr_num)
	AssumeFPS(Nfr_num, Nfr_den, False)		''# final sample rate:''
			[[AssumeSampleRate]](Ar)
			[[AssumeFPS]](Nfr_num, Nfr_den, False)
			</div>
			<div style="max-width:62em" >
			In the example above, the ''intermediate sample rate'' needs to be
			:(44100 * 24000 / 1001) / (25 * 1) = 42293.706294
			but because audio sample rates are always integers, 42293.706294 must be rounded to 42294, <br>
			which results in a time slippage of about 30ms per hour.
			</div>

	~~For exact resampling the intermediate samplerate needs to be 42293.706293 which if rounded to 42294 would causes about 30ms per hour variation.~~

	~~'''~~Changes~~:'''~~		== Changes ==
	{\| border="1"		{\| border="1"
	\|-		\|-

Raffriff42: added category

2015-11-08T15:30:14Z

added category

← Older revision		Revision as of 17:30, 8 November 2015
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	[[Category:Internal filters]]		[[Category:Internal filters]]
			[[Category:Audio_filters]]

Admin: 1 revision

2013-05-09T15:02:25Z

1 revision

← Older revision	Revision as of 17:02, 9 May 2013
(No difference)

Wilbert at 20:05, 29 March 2006

2006-03-29T20:05:04Z

New page

{{Template:FuncDef|ResampleAudio(clip, int new_rate_numerator [, int new_rate_denominator])}}

ResampleAudio performs a high-quality change of audio sample rate.
The conversion is skipped if the samplerate is already at the given rate.

When using fractional resampling the output audio samplerate is given by :

int(new_rate_numerator / new_rate_denominator + 0.5)

However the internally the resampling factor used is :

new_rate_numerator / (new_rate_denominator * old_sample_rate)

This causes the audio duration to vary slightly (which is generally what is desired).

Starting from v2.53 ResampleAudio accepts any number of channels.
Starting from v2.56 ResampleAudio process float samples directly. Support fractional resampling.

# Resamples audio to 48 kHz:
source = AviSource("c:\audio.wav")
return ResampleAudio(source, 48000)

# Exact 4% speed up for PAL telecine:
Nfr_num = 25
Nfr_den = 1
AviSource("C:\Film.avi") # 23.976 fps, 44100Hz
Ar = Audiorate()
ResampleAudio(Ar*FramerateNumerator()*Nfr_den, FramerateDenominator()*Nfr_num)
AssumeSampleRate(Ar)
AssumeFPS(Nfr_num, Nfr_den, False)

For exact resampling the intermediate samplerate needs to be 42293.706293 which if rounded to 42294 would causes about 30ms per hour variation.

'''Changes:'''
{| border="1"
|-
| v2.56
| Added new_sample_rate=float.
|}

[[Category:Internal filters]]