Talk:Proposal Change Speed Enhancements

Comments from Gale July 2011
Percent Change [ ] Change Factor [   ]  BPM or RPM: from [  ] to [   ]  [Add] Presets: [ to ]^| [Delete] Length: from [greyed] to [TimeTextCtrl] How the presets were handled depends on opinion and what's possible. I would envisage "Add" above might add the "from / to" value pair as a single preset and "Delete" might delete the selected preset. Or, we could have a history combo box as in "Specify Command Line Encoder" prefilled with the most common vinyl presets. User then adds their own presets as a freeform text entry using the syntax of the vinyl entries (this won't support "Add" or "Delete" buttons - we just set the max number of list rows). Or we just have a pair of unmodifiable preset combo boxes as now.  Steve 20 July 11: by "combo box" I mean a text box with attached drop down list Common Widgets Gale: Yes a "combo box" is another possibility pretty similar to the "history combo box" I described. But from what I think you envisage, the "presets" are decided by us and user can't add to them (or possibly add a single one if we write to .cfg)? With the "history box" user can add presets up to the limit of the history box. A separate single box for presets has a possible advantage of being less cumbersome for user than selecting or typing in both the "from" and "to" boxes. Steve 20 July 11: What's the user case for saving multiple user presets? I can see the benefit of the vinyl speed presets, and perhaps a "double speed", "half speed" and remembering the last used, but I would have thought that supporting multiple user defined presets would be a very small minority benefit and not worth the extra complication. Gale: I've seen several (acoustic shellac records with the exact speed, repeat sets of music samples requiring different BPM adjustment, scientific experiments with tones, exporting for broadcast use where different lengths or file sizes are required for different purposes but bit rate can't change...). I'm adding another e-mail vote for it now.) Steve 24Jul11: I think that if a user has a lot of shellac records that have the same speed (that is not 78) and another lot of records at another speed (also not 78) and want to use Audacity to correct the speed, then this would be a small niche use. Similarly for scientific experiments if a selection of speed ratio are required repeatedly. I think this minority use is covered as it is easy for the user to set up a Chain command for each setting that they want to use. If there are a significant number of users doing this type of thing, then a hint could be given in the manual for using Change Speed in a Chain. Gale 24Jul11: I think it depends on the difficulty of implementing extra functionality vs making it too complex for average user. There are almost as many FR votes for presets as a length control. I could understand that my idea of dedicated preset boxes could be thought of as overkill, but a history combo box doesn't make any more clutter than a standard combo box. Steve 25Jul11: If a History Combo Box still allows direct user text entry, and is not too difficult to implement then I think that would be useful. I could still add a note to the manual about using Change Speed in a Chain if you think there is sufficient demand, or perhaps better to write something in the wiki regarding the more general case of using a Chain command to save user settings for an effect? Gale 27Jul11: Look at "Options" when exporting as "(external program)" for a simple history combo box (Lame and FFmpeg presets are built-in but can be deleted by exceeding the list items limit). Not sure if you can make it never overwrite the built-in presets. I assume we will save the last used item whichever type of box we use. There is an example at "Custom FFmpeg Export" which initialises empty with a button to load the preset and also has XML import/export which would definitely be overkill for this. I don't think some of the people who want Change Speed presets would be satisfied with the Chains workaround but it's a good idea to mention it at EffectsTips - done. </ul></ul>
 * While I support the "Final Length" spinbox, I don't think we should remove vinyl presets, indeed I think we should have more presets. Removal of presets would prevent me supporting the current proposal.
 * Steve 20 July 11: The main point of this proposal is adding the "Final Length" spinbox. Re, the presets, I didn't think of it as being a "removal" of a feature - the only real change here is that "From" is "Initial Tempo" and "To" is "Final Tempo" and the values are no longer limited to only three options. How about if they were "combo boxes"?
 * Gale: There is a "loss" or "inconvenience" if user has to type in the values for rpm every time where they are accustomed to selecting a box (think of people trying to type "33 1/3" into the box). Clearly there is a "demand" for presets in their own right. See below.
 * I think a fundamental problem novices have with Change Speed/Tempo is the "Percent Change". A change factor (as used by Transcription Toolbar) would make these effects much more comfortable for them. Being able to choose a percent change based on knowing the required final length or the initial/final speed will help, but many users will still only know that they want to go half or twice as fast.
 * I think to match with "Change Tempo" and current "Change Speed", we should probably have Percent Change as the uppermost control. I would envisage something like: