Difference between revisions of "LAME -q switch"
From Hydrogenaudio Knowledgebase
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| − | = | + | =Internal Variables= |
{| border=1 class="wikitable" style="text-align:center" | {| border=1 class="wikitable" style="text-align:center" | ||
| − | ! -q n !! huffman search !! sv_qnt.substep_shaping !! subblock gain !! noise shaping !! amplification !! stopping | + | ! -q n !! huffman search !! full_outer_loop !! sv_qnt.substep_shaping !! subblock gain !! noise shaping !! amplification !! stopping !! description |
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| − | | 0 | + | | 0 || best || 1 || 2 || 1 || 1 || 2 || 1 || align="left" | Use slowest & best possible version of all algorithms. |
|- | |- | ||
| − | | 1 | + | | 1 || best || 0 || 2 || 1 || 1 || 2 || 1 || |
|- | |- | ||
| − | | 2 | + | | 2 || best || 0 || 2 || 1 || 1 || 1 || 1 || align="left" | Recommended. Same as -h. -q 0 and -q 1 are slow and may not produce significantly higher quality. |
|- | |- | ||
| − | | 3 | + | | 3 || best || 0 || ? || 1 || 1 || 1 || 1 || align="left" | Default value. Good speed, good quality. |
|- | |- | ||
| − | | 4 | + | | 4 || best || 0 || ? || 1 || 1 || 0 || 0 || |
|- | |- | ||
| − | | 5 | + | | 5-6 || normal || 0 || ? || 1 || 1 || 0 || 0 || |
|- | |- | ||
| − | | | + | | 7-8 || normal || 0 || ? || -1 || 0 || 0 || 0 || align="left" | Same as -f. Very fast, ok quality. (psycho acoustics are used for pre-echo & M/S, but no noise shaping is done. |
|- | |- | ||
| − | | | + | | 9 || normal || 0 || ? || -1 || 0 || 0 || 0 || align="left" | Disables almost all algorithms including psy-model. Poor quality. |
| + | |} | ||
| + | |||
| + | = VBR = | ||
| + | |||
| + | {| border=1 class="wikitable" | ||
| + | ! -q n !! description | ||
|- | |- | ||
| − | | | + | | 0-4 || Default value. Use the best algorithm. |
|- | |- | ||
| − | | 9 | + | | 5-6 || Use the not so good algorithm |
| + | |- | ||
| + | | 7-9 || | ||
|} | |} | ||
| − | + | =Observations= | |
| − | =CBR / ABR | + | * -q 5-6 Output Same Results. LAME header will indicate the different quality parameter. But the files are otherwise a perfect match. |
| + | * -q 7-8 Is always mapped to -q 7 and thus outputs identical files, including the LAME header. | ||
| + | * -q 9 Output is same as -q 7. But official doc describes it as a different quality. LAME header will be different for CBR/ABR and identical for VBR. | ||
Revision as of 13:56, 3 June 2013
Internal Variables
| -q n | huffman search | full_outer_loop | sv_qnt.substep_shaping | subblock gain | noise shaping | amplification | stopping | description |
|---|---|---|---|---|---|---|---|---|
| 0 | best | 1 | 2 | 1 | 1 | 2 | 1 | Use slowest & best possible version of all algorithms. |
| 1 | best | 0 | 2 | 1 | 1 | 2 | 1 | |
| 2 | best | 0 | 2 | 1 | 1 | 1 | 1 | Recommended. Same as -h. -q 0 and -q 1 are slow and may not produce significantly higher quality. |
| 3 | best | 0 | ? | 1 | 1 | 1 | 1 | Default value. Good speed, good quality. |
| 4 | best | 0 | ? | 1 | 1 | 0 | 0 | |
| 5-6 | normal | 0 | ? | 1 | 1 | 0 | 0 | |
| 7-8 | normal | 0 | ? | -1 | 0 | 0 | 0 | Same as -f. Very fast, ok quality. (psycho acoustics are used for pre-echo & M/S, but no noise shaping is done. |
| 9 | normal | 0 | ? | -1 | 0 | 0 | 0 | Disables almost all algorithms including psy-model. Poor quality. |
VBR
| -q n | description |
|---|---|
| 0-4 | Default value. Use the best algorithm. |
| 5-6 | Use the not so good algorithm |
| 7-9 |
Observations
- -q 5-6 Output Same Results. LAME header will indicate the different quality parameter. But the files are otherwise a perfect match.
- -q 7-8 Is always mapped to -q 7 and thus outputs identical files, including the LAME header.
- -q 9 Output is same as -q 7. But official doc describes it as a different quality. LAME header will be different for CBR/ABR and identical for VBR.
