Difference between revisions of "Nero AAC"
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| − | A commercial implementation of both LC AAC and HE AAC, Nero AAC is | + | A commercial implementation of both LC AAC and HE AAC, Nero AAC is produced by Nero AG as part of their Nero Digital line of products. It is generally precieved to have the highest quality [[VBR]] LC AAC implementation (although QuickTime bests it in [[CBR]] mode at 128kbps). The codec can also create HEv1/v2 AAC streams for extremely low bitrates and supports multi-channel surround sound encoding. As of May 2006, Nero AAC is availble for free as a commandline tool called "Nero Digital Audio". |
| − | Nero Digital. | + | |
| − | it in CBR at 128kbps). The codec also | + | |
| − | + | ||
| − | + | ||
| − | = | + | ==Command Line Options== |
| − | + | ===Usage=== | |
| + | neroAacEnc.exe [options] -if <input-file> -of <output-file> | ||
| − | + | <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. | |
| − | : | + | <output-file>: Path to output file to encode to, in MP4 format. |
| − | == | + | ===Quality/Bitrate Control=== |
| − | : - | + | '''-q <number>''': |
| + | Enables "target quality" mode. <number> is floating-point number between 1 and 10. | ||
| − | + | '''-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 none 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 more 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; optimal AAC profile is automatically determined from quality/bitrate settings when no override is specified. | ||
| + | |||
| + | '''-hinttrack''': Generates an RTP hint track in output MP4 file. | ||
| + | |||
| + | '''-ignorelength''': Ignores length signaled by WAV headers of input file. Useful for certain frontends using stdin. | ||
== External References == | == External References == | ||
Revision as of 12:30, 6 July 2006
A commercial implementation of both LC AAC and HE AAC, Nero AAC is produced by Nero AG as part of their Nero Digital line of products. It is generally precieved to have the highest quality VBR LC AAC implementation (although QuickTime bests it in CBR mode at 128kbps). The codec can also create HEv1/v2 AAC streams for extremely low bitrates and supports multi-channel surround sound encoding. As of May 2006, Nero AAC is availble for free as a commandline tool called "Nero Digital Audio".
Contents
Command Line Options
Usage
neroAacEnc.exe [options] -if <input-file> -of <output-file>
<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.
<output-file>: Path to output file to encode to, in MP4 format.
Quality/Bitrate Control
-q <number>: Enables "target quality" mode. <number> is floating-point number between 1 and 10.
-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 none 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 more 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; optimal AAC profile is automatically determined from quality/bitrate settings when no override is specified.
-hinttrack: Generates an RTP hint track in output MP4 file.
-ignorelength: Ignores length signaled by WAV headers of input file. Useful for certain frontends using stdin.
