SSRC - Revision history

Reel.Deal: add link to avs+ documentation

2022-09-18T04:56:33Z

add link to avs+ documentation

← Older revision		Revision as of 06:56, 18 September 2022
Line 1:		Line 1:
	<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/ssrc.html https://avisynthplus.readthedocs.io]
			</div>


	High quality audio sample rate converter by [http://shibatch.sourceforge.net/ Naoki Shibata]. This filter should result in better audio quality than [[ResampleAudio]] when converting between 44100↔48000 Hz.		High quality audio sample rate converter by [http://shibatch.sourceforge.net/ Naoki Shibata]. This filter should result in better audio quality than [[ResampleAudio]] when converting between 44100↔48000 Hz.
	<div {{BoxWidthIndent\|52\|1}} >		<div {{BoxWidthIndent\|52\|1}} >

Raffriff42: note AVS+ differences

2017-07-04T13:15:06Z

note AVS+ differences

← Older revision		Revision as of 15:15, 4 July 2017
Line 1:		Line 1:
	<div style="max-width:62em" >		<div style="max-width:62em" >
	High quality audio sample rate converter by [http://shibatch.sourceforge.net/ Naoki Shibata~~]. Audio is always converted to [[Float]~~]. This filter should result in better audio quality than [[ResampleAudio]] when converting between 44100↔48000 Hz.		High quality audio sample rate converter by [http://shibatch.sourceforge.net/ Naoki Shibata]. This filter should result in better audio quality than [[ResampleAudio]] when converting between 44100↔48000 Hz.
	<div {{BoxWidthIndent\|52\|1}} >		<div {{BoxWidthIndent\|52\|1}} >
	{{BoldColor\|blue\|120\|“}}44.1kHz sampling rate is used for a CD, and 48kHz is used for a DVD... Converting between these frequencies is hard, because the ratio between these two frequencies is 147:160, which are not small numbers. Accordingly, we need a very long FIR filter in order not to degrade the sound quality during conversion. This program utilizes FFTs to apply the FIR filter in order to reduce the amount of computation.{{BoldColor\|blue\|120\|”}} <sup>[http://shibatch.sourceforge.net/]</sup>		{{BoldColor\|blue\|120\|“}}44.1kHz sampling rate is used for a CD, and 48kHz is used for a DVD... Converting between these frequencies is hard, because the ratio between these two frequencies is 147:160, which are not small numbers. Accordingly, we need a very long FIR filter in order not to degrade the sound quality during conversion. This program utilizes FFTs to apply the FIR filter in order to reduce the amount of computation.{{BoldColor\|blue\|120\|”}} <sup>[http://shibatch.sourceforge.net/]</sup>
Line 16:		Line 16:
	:{{Par2\|clip\|clip\|}}		:{{Par2\|clip\|clip\|}}
	::Source clip. Audio is always converted to [[Float]].		::Source clip. Audio is always converted to [[Float]].
			::{{AvsPluscon}} no conversion is performed. Accepts [[Float]] audio only.

	:{{Par2\|samplerate\|int\|}}		:{{Par2\|samplerate\|int\|}}

Admin: /* Changes */

2016-05-01T16:45:54Z

Changes

← Older revision		Revision as of 18:45, 1 May 2016
Line 43:		Line 43:
	\| Initial Release.		\| Initial Release.
	\|}		\|}
	~~</div>~~

	Some parts of SSRC is:		Some parts of SSRC is:

Raffriff42: formatting

2016-02-28T10:26:18Z

formatting

← Older revision		Revision as of 12:26, 28 February 2016
Line 5:		Line 5:
	</div>		</div>
	Unlike [[ResampleAudio]], '''SSRC''' doesn't work for arbitrary sample rate ratios. If it cannot handle resampling between the two sample rates, an error is raised.		Unlike [[ResampleAudio]], '''SSRC''' doesn't work for arbitrary sample rate ratios. If it cannot handle resampling between the two sample rates, an error is raised.
			</div>


	== Syntax and Parameters ==		== Syntax and Parameters ==
			<div style="max-width:62em" >
	{{FuncDef		{{FuncDef
	\|SSRC(clip, int samplerate [, bool fast])		\|SSRC(clip, int samplerate [, bool fast])
	}}		}}

			:{{Par2\|clip\|clip\|}}
			::Source clip. Audio is always converted to [[Float]].

	:{{Par2\|samplerate\|int\|}}		:{{Par2\|samplerate\|int\|}}
Line 18:		Line 23:
	::Enable faster processing at slightly lower quality.		::Enable faster processing at slightly lower quality.
	::Set this to ''false'' if you are doing large-ratio rate conversions (more than a factor 2).		::Set this to ''false'' if you are doing large-ratio rate conversions (more than a factor 2).
			</div>


	== Examples ==		== Examples ==
			<div style="max-width:62em" >
	* Downsampling to 44.1 kHz:		* Downsampling to 44.1 kHz:
	<div {{BoxWidthIndent\|24\|2}} >		<div {{BoxWidthIndent\|24\|2}} >
	AviSource("c:\file.avi")		AviSource("c:\file.avi")
	SSRC(44100)		SSRC(44100)
			</div>
	</div>		</div>


	== Changes ==		== Changes ==
			<div style="max-width:62em" >
	{\| border="1"		{\| border="1"
	\|-		\|-
Line 34:		Line 43:
	\| Initial Release.		\| Initial Release.
	\|}		\|}
			</div>

	Some parts of SSRC is:		Some parts of SSRC is:

Raffriff42: formatting, links, phrasing

2016-02-15T04:45:30Z

formatting, links, phrasing

← Older revision		Revision as of 06:45, 15 February 2016
Line 1:		Line 1:
	{{~~Template~~:~~FuncDef\|SSRC(clip~~, ~~int samplerate [~~, ~~bool fast])~~}}		<div style="max-width:62em" >
			High quality audio sample rate converter by [http://shibatch.sourceforge.net/ Naoki Shibata]. Audio is always converted to [[Float]]. This filter should result in better audio quality than [[ResampleAudio]] when converting between 44100↔48000 Hz.
			<div {{BoxWidthIndent\|52\|1}} >
			{{BoldColor\|blue\|120\|“}}44.1kHz sampling rate is used for a CD, and 48kHz is used for a DVD... Converting between these frequencies is hard, because the ratio between these two frequencies is 147:160, which are not small numbers. Accordingly, we need a very long FIR filter in order not to degrade the sound quality during conversion. This program utilizes FFTs to apply the FIR filter in order to reduce the amount of computation.{{BoldColor\|blue\|120\|”}} <sup>[http://shibatch.sourceforge.net/]</sup>
			</div>
			Unlike [[ResampleAudio]], '''SSRC''' doesn't work for arbitrary sample rate ratios. If it cannot handle resampling between the two sample rates, an error is raised.

	''SSRC'' resampling. Audio is always converted to float. This filter will result in better audio quality than [[ResampleAudio]]. It uses SSRC by [http://shibatch.sourceforge.net/ Naoki Shibata], which offers the best resample quality available.

	~~Sampling rates of 44.1kHz~~ and ~~48kHz are popularly used~~, ~~but the ratio of these two frequencies is 147:160~~, and they are not a small numbers. Therefore, sampling rate conversion without degradation of sound quality requires filter with very large order, and it's difficult to achieve both quality and speed. This program achieves relatively fast ~~and high quality with two different kinds of filters combined skillfully.~~		== Syntax and Parameters ==
			{{FuncDef
			\|SSRC(clip, int samplerate [, bool fast])
			}}

	~~'''Parameter~~:~~'''~~		:{{Par2\|samplerate\|int\|}}
	{~~\| border="1"~~		::Target sample rate.
	\|-
	\| samplerate
	\| ~~samplerate must be an integer.~~
	\|-
	~~\| fast~~
	~~\| This will enable faster processing at slightly lower quality. Set this to false if you are doing large~~ sample rate ~~conversions (more than a factor 2)~~. ~~Default: true.~~
	\|}

	~~SSRC doesn~~'~~t work for arbitrary ratios of the samplerate of the source and target clip. The following ratios~~ are ~~allowed~~ (~~see SSRC~~.~~cpp):~~		:{{Par2\|fast\|bool\|true}}
			::Enable faster processing at slightly lower quality.
			::Set this to ''false'' if you are doing large-ratio rate conversions (more than a factor 2).

	~~sfrq = samplerate of source clip~~
	~~dfrq = samplerate of destination clip~~
	~~frqgcd = gcd(sfrq,dfrq) # Greatest Common Divisor~~
	~~fs1 = (dfrq > sfrq) ? sfrq / frqgcd : dfrq / frggcd~~
	~~Resampling is possible if: (fs1 == 1) or (fs1 % 2 == 0) or (fs1 % 3 == 0)~~

	~~example for which resampling is possible:~~
	~~sfrq = 44.1 kHz~~
	~~dfrq = 48 kHz~~
	~~frqgcd = gcd(44100,48000) = 300~~
	~~dfrq > sfrq, hence~~
	~~fs1 = sfrq / frqgcd = sfrq / gcd(sfrq,dfrq) = 44100/300 = 147~~
	~~and 147%3=0 since 147 = 3 * 49~~

	~~The samplerate of your source clip can be found as follows~~		== Examples ==
			* Downsampling to 44.1 kHz:
	~~AviSource(...)~~		<div {{BoxWidthIndent\|24\|2}} >
	~~Subtitle(string(AssumeFPS(23.976,sync_audio~~=~~true).AudioRate))~~


	~~'''Example:'''~~

	# Downsampling to 44.1 kHz:
	AviSource("c:\file.avi")		AviSource("c:\file.avi")
	SSRC(44100)		SSRC(44100)
			</div>


	~~'''~~Changes~~:'''~~		== Changes ==
	{\| border="1"		{\| border="1"
	\|-		\|-
Line 54:		Line 39:
	Copyright (C) 2001-2003, Peter Pawlowski		Copyright (C) 2001-2003, Peter Pawlowski
	All rights reserved.		All rights reserved.
			</div>


	[[Category:Internal filters]]		[[Category:Internal filters]]
	[[Category:Audio_filters]]		[[Category:Audio_filters]]

Raffriff42: added category

2015-11-08T15:30:48Z

added category

← Older revision		Revision as of 17:30, 8 November 2015
Line 57:		Line 57:

	[[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 14:38, 15 April 2012

2012-04-15T14:38:11Z

New page

{{Template:FuncDef|SSRC(clip, int samplerate [, bool fast])}}

''SSRC'' resampling. Audio is always converted to float. This filter will result in better audio quality than [[ResampleAudio]]. It uses SSRC by [http://shibatch.sourceforge.net/ Naoki Shibata], which offers the best resample quality available.

Sampling rates of 44.1kHz and 48kHz are popularly used, but the ratio of these two frequencies is 147:160, and they are not a small numbers. Therefore, sampling rate conversion without degradation of sound quality requires filter with very large order, and it's difficult to achieve both quality and speed. This program achieves relatively fast and high quality with two different kinds of filters combined skillfully.

'''Parameter:'''
{| border="1"
|-
| samplerate
| samplerate must be an integer.
|-
| fast
| This will enable faster processing at slightly lower quality. Set this to false if you are doing large sample rate conversions (more than a factor 2). Default: true.
|}

SSRC doesn't work for arbitrary ratios of the samplerate of the source and target clip. The following ratios are allowed (see SSRC.cpp):

sfrq = samplerate of source clip
dfrq = samplerate of destination clip
frqgcd = gcd(sfrq,dfrq) # Greatest Common Divisor
fs1 = (dfrq > sfrq) ? sfrq / frqgcd : dfrq / frggcd
Resampling is possible if: (fs1 == 1) or (fs1 % 2 == 0) or (fs1 % 3 == 0)

example for which resampling is possible:
sfrq = 44.1 kHz
dfrq = 48 kHz
frqgcd = gcd(44100,48000) = 300
dfrq > sfrq, hence
fs1 = sfrq / frqgcd = sfrq / gcd(sfrq,dfrq) = 44100/300 = 147
and 147%3=0 since 147 = 3 * 49

The samplerate of your source clip can be found as follows

AviSource(...)
Subtitle(string(AssumeFPS(23.976,sync_audio=true).AudioRate))

'''Example:'''

# Downsampling to 44.1 kHz:
AviSource("c:\file.avi")
SSRC(44100)

'''Changes:'''
{| border="1"
|-
| v2.54
| Initial Release.
|}

Some parts of SSRC is:

Copyright (C) 2001-2003, Peter Pawlowski
All rights reserved.

[[Category:Internal filters]]