Opus Recommended Settings - Revision history

MarkH: fix broken demo3 link

2024-11-25T15:10:24Z

fix broken demo3 link

← Older revision		Revision as of 15:10, 25 November 2024
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	\|6 (5.1 surround)		\|6 (5.1 surround)
	\|128 - 256		\|128 - 256
	\|rowspan="2"\|For surround sound, Opus uses '''[https://xiph.org/~xiphmont/demo/opus/demo3.shtml surround-sound bitrate allocation]'''.		\|rowspan="2"\|For surround sound, Opus uses '''[https://people.xiph.org/~xiphmont/demo/opus/demo3.shtml surround-sound bitrate allocation]'''.
	\|-		\|-
	\|8 (7.1 surround)		\|8 (7.1 surround)

MrZeus: /* Mono or Stereo */ tweak mono/stereo threshhold according to current source code

2018-12-14T13:15:23Z

Mono or Stereo: tweak mono/stereo threshhold according to current source code

← Older revision		Revision as of 13:15, 14 December 2018
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	== Mono or Stereo ==		== Mono or Stereo ==
	Opus tends to start '''downmixing stereo inputs to mono''' from roughly '''24 Kb/s and lower'''.		Opus tends to start '''downmixing stereo inputs to mono''' from roughly '''19 Kb/s and lower'''.
	You can check the details in the '''[https://github.com/xiph/opus/blob/master/src/opus_encoder.c#~~L148~~ opus_encoder.c]''' source file.		You can check the details in the '''[https://github.com/xiph/opus/blob/master/src/opus_encoder.c#L149 opus_encoder.c]''' source file.

	You can force downmixing at any bitrate by using the following command-line parameters:		You can force downmixing at any bitrate by using the following command-line parameters:

Jmspeex at 18:34, 30 May 2017

2017-05-30T18:34:01Z

← Older revision		Revision as of 18:34, 30 May 2017
Line 132:		Line 132:
	For real-time applications, sending fewer packets per second reduces the overall bitrate, since it reduces the overhead from '''[https://en.wikipedia.org/wiki/IPv6_packet#Fixed_header IP]''', '''[https://en.wikipedia.org/wiki/User_Datagram_Protocol#Packet_structure UDP]''', and '''[https://en.wikipedia.org/wiki/Real-time_Transport_Protocol#Packet_header RTP headers]'''.		For real-time applications, sending fewer packets per second reduces the overall bitrate, since it reduces the overhead from '''[https://en.wikipedia.org/wiki/IPv6_packet#Fixed_header IP]''', '''[https://en.wikipedia.org/wiki/User_Datagram_Protocol#Packet_structure UDP]''', and '''[https://en.wikipedia.org/wiki/Real-time_Transport_Protocol#Packet_header RTP headers]'''.
	However, it increases latency and sensitivity to packet losses, as losing one packet constitutes a loss of a bigger chunk of audio.		However, it increases latency and sensitivity to packet losses, as losing one packet constitutes a loss of a bigger chunk of audio.
	~~Increasing the frame duration also slightly improves coding efficiency~~, ~~but the gain becomes small for~~ frame sizes above 20~~ ~~ms.		Unless operating at very low bitrates over RTP, there is no reason to use frame sizes above 20 ms, as those will have slightly lower quality for music encoding.

	For these reasons, the default 20 ms frames are a good choice for most applications.		For these reasons, the default 20 ms frames are a good choice for most applications.

MrZeus: /* Bandwidth Transition Thresholds */ stop hiding bandwidth ranges under attr tags

2016-12-14T14:37:17Z

Bandwidth Transition Thresholds: stop hiding bandwidth ranges under attr tags

← Older revision		Revision as of 14:37, 14 December 2016
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	{\| class="wikitable" style="text-align:center"		{\| class="wikitable" style="text-align:center"
	\|-		\|-
	\|~~rowspan~~="2"\|(~~bitrates in ~~Kb/s)		!rowspan="3"\|Bandpass Range (Hz)
			!colspan="4"\|Rough Bitrate Required (Kb/s)
			\|-
	!colspan="2"\|Mono		!colspan="2"\|Mono
	!colspan="2"\|Stereo		!colspan="2"\|Stereo
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	!Music		!Music
	\|-		\|-
	~~!<abbr title~~="(3-~~4000~~ Hz)~~">NarrowBand</abbr>~~		\|style="text-align:right;"\|NarrowBand (3 - 4000)
	\|12		\|12
	\|15		\|15
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	\|?		\|?
	\|-		\|-
	~~!<abbr title~~="(3-~~6000~~ Hz)~~">MediumBand</abbr>~~		\|style="text-align:right;"\|MediumBand (3 - 6000)
	\|15		\|15
	\|18-22		\|18-22
Line 100:		Line 102:
	\|?		\|?
	\|-		\|-
	~~!<abbr title~~="(3-~~8000~~ Hz)~~">WideBand</abbr>~~		\|style="text-align:right;"\|WideBand (3 - 8000)
	\|16-20		\|16-20
	\|22-28		\|22-28
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	\|?		\|?
	\|-		\|-
	~~!<abbr title~~="(3-12000~~ Hz~~)~~">SuperWideBand</abbr>~~		\|style="text-align:right;"\|SuperWideBand (3-12000)
	\|24-28		\|24-28
	\|28-32		\|28-32
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	\|?		\|?
	\|-		\|-
	~~!<abbr title~~="(3-20000~~ Hz~~)~~">FullBand</abbr>~~		\|style="text-align:right;"\|FullBand (3-20000)
	\|28-40		\|28-40
	\|32-64		\|32-64

MrZeus: /* Recommended Bitrates */ slight reformatting, adding nbsp's for number ranges

2016-11-09T12:35:07Z

Recommended Bitrates: slight reformatting, adding nbsp's for number ranges

← Older revision		Revision as of 12:35, 9 November 2016
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	The settings in the table below are meant to '''start you off''' with a decent tradeoff between '''good quality''' and '''small file size''' (or '''bitrate usage''', if you're streaming).		The settings in the table below are meant to '''start you off''' with a decent tradeoff between '''good quality''' and '''small file size''' (or '''bitrate usage''', if you're streaming).

	You should test the suggested bitrate by actually '''listening''' to your encoded audio and then tweaking the bitrate:		You should test the suggested bitrate by actually '''listening''' to your encoded audio and then:
	* '''down''' if you think the quality is good, but the file size (or bitrate) is too big		* tweaking the bitrate '''down''' if you think the quality is good, but the file size (or bitrate) is too big,
	* '''up''' if you think the quality is bad, and you can afford having bigger files (or a larger streaming bitrate)		* tweaking the bitrate '''up''' if you think the quality is bad, and you can afford having bigger files (or a larger streaming bitrate).

	{\| class="wikitable" style="text-align:center"		{\| class="wikitable" style="text-align:center"
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	\|1 (mono)		\|1 (mono)
	\|Use '''[http://www.rowetel.com/?page_id=452 Codec 2]'''		\|Use '''[http://www.rowetel.com/?page_id=452 Codec 2]'''
	\|Opus only supports bitrates down to 6 Kb/s. Codec 2 handles ultra low bitrate speech ~~from~~ 0.7 to 3.2 Kb/s.		\|Opus only supports bitrates '''down to 6 Kb/s'''.<br>
			Codec 2 handles ultra low bitrate speech at '''0.7 - 3.2 Kb/s'''.
	\|-		\|-
	\|VoIP		\|VoIP
	\|1		\|1
	\|10-24		\|10 - 24
	\|10 Kb/s will deliver narrowband most of the time, 24 Kb/s should give fullband.<br>		\|10 Kb/s will deliver narrowband most of the time, 24 Kb/s should give fullband.<br>
	More details in '''[[Opus_Recommended_Settings#Bandwidth_Transition_Thresholds\|the relevant table]]''' further down this page.		More details in '''[[Opus_Recommended_Settings#Bandwidth_Transition_Thresholds\|the relevant table]]''' further down this page.
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	\|Music Streaming / Radio		\|Music Streaming / Radio
	\|2		\|2
	\|64-96		\|64 - 96
	\|Opus has better quality than MP3, AAC and [[Vorbis]] at these rates.<br>		\|Opus has better quality than MP3, AAC and [[Vorbis]] at these rates.<br>
	(listening test results: '''[http://listening-tests.hydrogenaud.io/igorc/results.html 64 Kb/s]''', '''[http://listening-test.coresv.net/results.htm 96 Kb/s]''')		(listening test results: '''[http://listening-tests.hydrogenaud.io/igorc/results.html 64 Kb/s]''', '''[http://listening-test.coresv.net/results.htm 96 Kb/s]''')
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	\|rowspan="3"\|Music Storage		\|rowspan="3"\|Music Storage
	\|2		\|2
	\|96-128		\|96 - 128
	\|Opus at 128 KB/s (VBR) is pretty much '''[https://en.wikipedia.org/wiki/Transparency_(data_compression) transparent]'''.		\|Opus at 128 KB/s (VBR) is pretty much '''[https://en.wikipedia.org/wiki/Transparency_(data_compression) transparent]'''.
	\|-		\|-
	\|6 (5.1 surround)		\|6 (5.1 surround)
	\|128-256		\|128 - 256
	\|rowspan="2"\|For surround sound, Opus uses '''[https://xiph.org/~xiphmont/demo/opus/demo3.shtml surround-sound bitrate allocation]'''.		\|rowspan="2"\|For surround sound, Opus uses '''[https://xiph.org/~xiphmont/demo/opus/demo3.shtml surround-sound bitrate allocation]'''.
	\|-		\|-
	\|8 (7.1 surround)		\|8 (7.1 surround)
	\|256-450		\|256 - 450
	\|-		\|-
	\|Music Archiving		\|Music Archiving
	\|1-8		\|1 - 8
	\|Use '''[[FLAC]]'''		\|Use '''[[FLAC]]'''
	\|If you are archiving audio, use a '''[https://en.wikipedia.org/wiki/Audio_file_format#Lossless_compressed_audio_format lossless audio format]''' to prevent '''[https://en.wikipedia.org/wiki/Generation_loss generation loss]'''.		\|If you are archiving audio, use a '''[https://en.wikipedia.org/wiki/Audio_file_format#Lossless_compressed_audio_format lossless audio format]''' to prevent '''[https://en.wikipedia.org/wiki/Generation_loss generation loss]'''.

MrZeus: /* Recommended Bitrates */ capitalisation, label listening test results with bitrate

2016-11-09T11:32:38Z

Recommended Bitrates: capitalisation, label listening test results with bitrate

← Older revision		Revision as of 11:32, 9 November 2016
Line 17:		Line 17:
	\|Low bandwidth HF/VHF digital radio		\|Low bandwidth HF/VHF digital radio
	\|1 (mono)		\|1 (mono)
	\|~~use~~ '''[http://www.rowetel.com/?page_id=452 Codec 2]'''		\|Use '''[http://www.rowetel.com/?page_id=452 Codec 2]'''
	\|Opus only supports bitrates down to 6 Kb/s. Codec 2 handles ultra low bitrate speech from 0.7 to 3.2 Kb/s.		\|Opus only supports bitrates down to 6 Kb/s. Codec 2 handles ultra low bitrate speech from 0.7 to 3.2 Kb/s.
	\|-		\|-
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	\|1		\|1
	\|10-24		\|10-24
	\|10 Kb/s will deliver narrowband most of the time, 24 Kb/s should give fullband.<br>More details in '''[[Opus_Recommended_Settings#Bandwidth_Transition_Thresholds\|the relevant table]]''' further down this page.		\|10 Kb/s will deliver narrowband most of the time, 24 Kb/s should give fullband.<br>
			More details in '''[[Opus_Recommended_Settings#Bandwidth_Transition_Thresholds\|the relevant table]]''' further down this page.
	\|-		\|-
	\|rowspan="2"\|Audiobooks / Podcasts		\|rowspan="2"\|Audiobooks / Podcasts
	\|1		\|1
	\|24		\|24
	\|~~bitrates~~ from here on up tend to deliver fullband audio.		\|Bitrates from here on up tend to deliver fullband audio.
	\|-		\|-
	\|2 (stereo)		\|2 (stereo)
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	\|2		\|2
	\|64-96		\|64-96
	\|Opus has better quality than MP3, AAC and [[Vorbis]] at these rates.<br>(test results '''[http://listening-tests.hydrogenaud.io/igorc/results.html ~~here~~]''' ~~and~~ '''[http://listening-test.coresv.net/results.htm ~~here~~]''')		\|Opus has better quality than MP3, AAC and [[Vorbis]] at these rates.<br>
			(listening test results: '''[http://listening-tests.hydrogenaud.io/igorc/results.html 64 Kb/s]''', '''[http://listening-test.coresv.net/results.htm 96 Kb/s]''')
	\|-		\|-
	\|rowspan="3"\|Music Storage		\|rowspan="3"\|Music Storage
	\|2		\|2
	\|96-128		\|96-128
	\|Opus at 128 KB/s (VBR) is pretty much '''[https://en.wikipedia.org/wiki/Transparency_(data_compression) transparent]'''		\|Opus at 128 KB/s (VBR) is pretty much '''[https://en.wikipedia.org/wiki/Transparency_(data_compression) transparent]'''.
	\|-		\|-
	\|6 (5.1 surround)		\|6 (5.1 surround)
	\|128-256		\|128-256
	\|rowspan="2"\|~~for~~ surround sound, Opus uses '''[https://xiph.org/~xiphmont/demo/opus/demo3.shtml surround-sound bitrate allocation]'''		\|rowspan="2"\|For surround sound, Opus uses '''[https://xiph.org/~xiphmont/demo/opus/demo3.shtml surround-sound bitrate allocation]'''.
	\|-		\|-
	\|8 (7.1 surround)		\|8 (7.1 surround)
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	\|Music Archiving		\|Music Archiving
	\|1-8		\|1-8
	\|~~use~~ '''[[FLAC]]'''		\|Use '''[[FLAC]]'''
	\|if you are archiving audio, use a '''[https://en.wikipedia.org/wiki/Audio_file_format#Lossless_compressed_audio_format lossless audio format]''' to prevent '''[https://en.wikipedia.org/wiki/Generation_loss generation loss]'''		\|If you are archiving audio, use a '''[https://en.wikipedia.org/wiki/Audio_file_format#Lossless_compressed_audio_format lossless audio format]''' to prevent '''[https://en.wikipedia.org/wiki/Generation_loss generation loss]'''.
	\|}		\|}

MarkH: /* Recommended Bitrates */ FLAC supports only 1-8 channels

2016-11-08T15:08:25Z

Recommended Bitrates: FLAC supports only 1-8 channels

← Older revision		Revision as of 15:08, 8 November 2016
Line 52:		Line 52:
	\|-		\|-
	\|Music Archiving		\|Music Archiving
	\|~~any~~		\|1-8
	\|use '''[[FLAC]]'''		\|use '''[[FLAC]]'''
	\|if you are archiving audio, use a '''[https://en.wikipedia.org/wiki/Audio_file_format#Lossless_compressed_audio_format lossless audio format]''' to prevent '''[https://en.wikipedia.org/wiki/Generation_loss generation loss]'''		\|if you are archiving audio, use a '''[https://en.wikipedia.org/wiki/Audio_file_format#Lossless_compressed_audio_format lossless audio format]''' to prevent '''[https://en.wikipedia.org/wiki/Generation_loss generation loss]'''

MarkH: /* Recommended Bitrates */ fix Codec2 URL, and clarify: not all ham radio uses want ultra low bitrate

2016-11-08T15:03:37Z

Recommended Bitrates: fix Codec2 URL, and clarify: not all ham radio uses want ultra low bitrate

← Older revision		Revision as of 15:03, 8 November 2016
Line 1:		Line 1:
	= Recommended Bitrates =		= Recommended Bitrates =
	Depending on ~~what kinds~~ of ~~sounds~~ you want to encode with Opus, you ~~should~~ use different bitrate (quality) settings.		Depending on the kind of audio you want to encode with Opus, you may want to use different bitrate (quality) settings.

	The settings in the table below are meant to '''start you off''' with a decent tradeoff between '''good quality''' and '''small ~~filesize~~''' (or '''bitrate usage''', if you're streaming).		The settings in the table below are meant to '''start you off''' with a decent tradeoff between '''good quality''' and '''small file size''' (or '''bitrate usage''', if you're streaming).

	You should test the suggested bitrate by actually '''listening''' to your encoded audio and then tweaking the bitrate:		You should test the suggested bitrate by actually '''listening''' to your encoded audio and then tweaking the bitrate:
	* '''down''' if you think the quality is good, but the ~~filesize~~ (or bitrate) is too big		* '''down''' if you think the quality is good, but the file size (or bitrate) is too big
	* '''up''' if you think the quality is bad, and you can afford having bigger files (or a larger streaming bitrate)		* '''up''' if you think the quality is bad, and you can afford having bigger files (or a larger streaming bitrate)

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	!Notes		!Notes
	\|-		\|-
	\|~~Ham~~ radio		\|Low bandwidth HF/VHF digital radio
	\|1 (mono)		\|1 (mono)
	\|use '''[http://www.rowetel.com~~/blog~~/?page_id=452 Codec 2]'''		\|use '''[http://www.rowetel.com/?page_id=452 Codec 2]'''
	\|Opus only supports bitrates down to 6 Kb/s. Codec 2 handles speech from 0.7 to 3.2 Kb/s.		\|Opus only supports bitrates down to 6 Kb/s. Codec 2 handles ultra low bitrate speech from 0.7 to 3.2 Kb/s.
	\|-		\|-
	\|VoIP		\|VoIP

MarkH: /* Trading Coding Efficiency with CPU Time */ not really lots, try video encoding for that!

2016-11-08T14:44:19Z

Trading Coding Efficiency with CPU Time: not really lots, try video encoding for that!

← Older revision		Revision as of 14:44, 8 November 2016
Line 132:		Line 132:

	== Trading Coding Efficiency with CPU Time ==		== Trading Coding Efficiency with CPU Time ==
	The Opus encoder uses its maximum algorithmic '''complexity''' setting of '''10''' '''[https://tools.ietf.org/html/rfc6716#section-2.1.5 by default]'''. This means ~~is uses lots of~~ CPU to give you the best quality encoding at a given bitrate.		The Opus encoder uses its maximum algorithmic '''complexity''' setting of '''10''' '''[https://tools.ietf.org/html/rfc6716#section-2.1.5 by default]'''. This means that it does not hesitate to use CPU to give you the best quality encoding at a given bitrate.

	If the CPU usage is too high for the system you are using Opus on, you can try a lower complexity setting. The allowed values span from '''10''' (highest CPU usage and quality) down to '''0''' (lowest CPU usage and quality).		If the CPU usage is too high for the system you are using Opus on, you can try a lower complexity setting. The allowed values span from '''10''' (highest CPU usage and quality) down to '''0''' (lowest CPU usage and quality).

	[[Category:Opus]]		[[Category:Opus]]

MrZeus: add the beginnings of a Complexity section, just to explain it simply to the casual users

2016-11-08T12:12:04Z

add the beginnings of a Complexity section, just to explain it simply to the casual users

← Older revision		Revision as of 12:12, 8 November 2016
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			= Recommended Bitrates =
	Depending on what kinds of sounds you want to encode with Opus, you should use different bitrate (quality) settings.		Depending on what kinds of sounds you want to encode with Opus, you should use different bitrate (quality) settings.

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	For these reasons, the default 20 ms frames are a good choice for most applications.		For these reasons, the default 20 ms frames are a good choice for most applications.

			== Trading Coding Efficiency with CPU Time ==
			The Opus encoder uses its maximum algorithmic '''complexity''' setting of '''10''' '''[https://tools.ietf.org/html/rfc6716#section-2.1.5 by default]'''. This means is uses lots of CPU to give you the best quality encoding at a given bitrate.

			If the CPU usage is too high for the system you are using Opus on, you can try a lower complexity setting. The allowed values span from '''10''' (highest CPU usage and quality) down to '''0''' (lowest CPU usage and quality).

	[[Category:Opus]]		[[Category:Opus]]