NeroAAC: Difference between revisions
| Line 47: | Line 47: | ||
Quality/bitrate control: | Quality/bitrate control: | ||
; -q <number> | ; <tt>-q <number></tt> | ||
: Enables "target quality" mode.<br><number> is a floating-point number in 0...1 range. I.e. 0.5 or 0.75, etc. with 1 being the highest quality and thus also having the largest output file size. | : Enables "target quality" mode.<br><tt><number></tt> is a floating-point number in 0...1 range. I.e. 0.5 or 0.75, etc. with 1 being the highest quality and thus also having the largest output file size. | ||
; -br <number> | ; <tt>-br <number></tt> | ||
: Specifies "target bitrate" mode.<br><number> is target bitrate in bits per second. | : Specifies "target bitrate" mode.<br><tt><number></tt> is target bitrate in bits per second. | ||
; -cbr <number> | ; <tt>-cbr <number></tt> | ||
: Specifies "target bitrate (streaming)" mode.<br><number> is target bitrate in bits per second. | : Specifies "target bitrate (streaming)" mode.<br><tt><number></tt> is target bitrate in bits per second. | ||
When neither of above quality/bitrate options is used, the encoder defaults to equivalent of <tt>-q 0.5</tt> | |||
Multipass encoding: | Multipass encoding: | ||
; -2pass | ; <tt>-2pass</tt> | ||
: Enables two-pass encoding mode.<br>Note that two-pass mode requires a physical file as input, rather than stdin. | : Enables two-pass encoding mode.<br>Note that two-pass mode requires a physical file as input, rather than stdin. | ||
; -2passperiod <number> | ; <tt>-2passperiod <number></tt> | ||
: Overrides two-pass encoding bitrate averaging period, in milliseconds.<br>Specify zero to use least restrictive value possible (default). | : Overrides two-pass encoding bitrate averaging period, in milliseconds.<br>Specify zero to use least restrictive value possible (default). | ||
Advanced features / troubleshooting: | Advanced features / troubleshooting: | ||
; -lc | ; <tt>-lc</tt> | ||
: Forces use of LC AAC profile (HE features disabled). | : Forces use of LC AAC profile (HE features disabled). | ||
; -he | ; <tt>-he</tt> | ||
: Forces use of HE AAC profile (HEv2 features disabled). | : Forces use of HE AAC profile (HEv2 features disabled). | ||
; -hev2 | ; <tt>-hev2</tt> | ||
: Forces use of HEv2 AAC profile | : Forces use of HEv2 AAC profile | ||
''Note that the above switches (-lc, -he, -hev2) should not be used'' | ''Note that the above switches (-lc, -he, -hev2) should not be used''. The optimal AAC profile is automatically determined from quality/bitrate settings when no override is specified. | ||
; -ignorelength | ; <tt>-ignorelength</tt> | ||
: Ignores length signaled by WAV headers of input file. Useful for certain frontends using stdin. | : Ignores length signaled by WAV headers of input file. Useful for certain frontends using stdin. | ||
Revision as of 17:25, 30 November 2010
| Developer(s) | Nero AG |
| Release information | |
|---|---|
| Stable release | 1.5.4.0 (Feb 18. 2010) |
| Preview release | n/a |
| Compatibility | |
| Operating system | Windows, Linux |
| Additional information | |
| Use | Encoder/Decoder |
| License | see site for license |
| Website | Nero AAC Codec |
The Nero AAC codec has been made freely available by Nero AG for personal non-commercial and/or technology-evaluation purposes. It is a set of three command-line tools that are used to encode, decode and apply tags to MP4 files. The download contains binaries for both Windows and Linux. It is the same codec that is used in Nero's other, commercial products.
The three command-line tools are:
- NeroAacEnc
- NeroAacDec
- NeroAacTag
This article is still a work in progress
NeroAacEnc
This is the encoder command-line tool. It is currently at version 1.5.4.0 and was last updated Feb 18th, 2010.
Usage
Windows
neroAacEnc.exe [options] -if <input-file> -of <output-file>
Linux:
./neroAacEnc [options] -if <input-file> -of <output-file>
Note: Make sure the binary is executable
Where:
- <input-file>
- Path to source file to encode.
The file must be in Microsoft WAV format and contain PCM data.
Specify - to encode from stdin.
Note that multiple input files can be specified, they will be encoded together into a single output file with chapter marks indicating source file divisions. - <output-file>
- Path to output file to encode to, in MP4 format.
Options:
Quality/bitrate control:
- -q <number>
- Enables "target quality" mode.
<number> is a floating-point number in 0...1 range. I.e. 0.5 or 0.75, etc. with 1 being the highest quality and thus also having the largest output file size. - -br <number>
- Specifies "target bitrate" mode.
<number> is target bitrate in bits per second. - -cbr <number>
- Specifies "target bitrate (streaming)" mode.
<number> is target bitrate in bits per second.
When neither of above quality/bitrate options is used, the encoder defaults to equivalent of -q 0.5
Multipass encoding:
- -2pass
- Enables two-pass encoding mode.
Note that two-pass mode requires a physical file as input, rather than stdin. - -2passperiod <number>
- Overrides two-pass encoding bitrate averaging period, in milliseconds.
Specify zero to use least restrictive value possible (default).
Advanced features / troubleshooting:
- -lc
- Forces use of LC AAC profile (HE features disabled).
- -he
- Forces use of HE AAC profile (HEv2 features disabled).
- -hev2
- Forces use of HEv2 AAC profile
Note that the above switches (-lc, -he, -hev2) should not be used. The optimal AAC profile is automatically determined from quality/bitrate settings when no override is specified.
- -ignorelength
- Ignores length signaled by WAV headers of input file. Useful for certain frontends using stdin.