Ticket #3405 (closed enhancement: fixed)
Opened 6 years ago
Last modified 4 years ago
ALSA input for analog capture
| Reported by: | anonymous | Owned by: | janne |
|---|---|---|---|
| Priority: | minor | Milestone: | 0.22 |
| Component: | mythtv | Version: | head |
| Severity: | medium | Keywords: | |
| Cc: | Ticket locked: | no |
Description
Currently, mythtv only supports OSS for analog capture. Since ALSA is the main audio system for Linux (2.6.0+), mythtv should alsa support ALSA capture.
Attachments
Change History
Changed 6 years ago by amistry@…
- Attachment mythtv_alsa.patch added
Changed 6 years ago by amistry@…
- Attachment mythtv_alsa-2.patch added
Further adhere to coding standards
comment:1 Changed 6 years ago by stuarta
- Version changed from unknown to head
- Milestone changed from unknown to 0.21
OSSAudioInput::OpenDevice?() is broken.
If the device open fails it throws a verbose error but then continues on it's merry way.
It repeatedly checks if (0 <= retval) and while it is reusing retval it just looks plain wrong.
Stuart
comment:2 Changed 6 years ago by amistry@…
Stuart: You're right, it is broken, but only with respect to logging info. The point of the repeated checking is to give the function a single return point at the end of the function. This way, I only have to do any potential cleanup at one point, at the end. All the 'if (0 <= retval)' is there to make sure further code only executes if everything up until that point is OK. If it's not, it'll be skipped and a return code of < 0 (usually -1) will signify an error. You'll notice all the functions I've wrote are like that inclusing the alsa input. If for some reason this is unacceptable, I can rework the patch to put returns after each error instead of just at the end.
comment:3 Changed 6 years ago by danielk
- Owner changed from ijr to danielk
- Type changed from patch to enhancement
Changed 6 years ago by danielk
- Attachment 3405-v1.patch added
Cleans up error handling, moves from libmythtv to libmyth so mythphone can use it evenually.
Changed 5 years ago by danielk
- Attachment 3405-v2.patch added
This just updates the patch for the current trunk. It still needs to handle error conditions better.
comment:5 Changed 5 years ago by Alan Calvert <cal@…>
Presenting patch alsa_input_3405-v3-trunk-18043:
I've use this patch on three systems for over a year, so I'm interested in it's welfare. This little effort started as a refresh to current trunk, but it sort of morphed beyond that. Perhaps I've addressed some of danielk's concerns over error handling. Subjectively, I believe it holds synch better than anything else I've tried. Objectively, it seems to work ok, and does pretty much all the things it needs to do to perform respectably. Enjoy.
Changed 5 years ago by Alan Calvert <cal@…>
- Attachment alsa_input_3405-v3-trunk-18043.patch.gz added
comment:6 Changed 5 years ago by Alan Calvert <cal@…>
v3 was pretty rough, v4 is a bit nicer.
comment:8 Changed 4 years ago by janne
- Owner changed from danielk to janne
- Status changed from assigned to accepted
comment:9 Changed 4 years ago by Alan Calvert <cal@…>
3405-v5 refresh to 19944, some tweaks & tidies, and reinstate alsa device selection (it fell off).
comment:10 in reply to: ↑ description Changed 4 years ago by anonymous
Any update on this?
Kernels built without OSS support are becoming more common (like in Fedora 11) so it's an actual problem now.
comment:11 Changed 4 years ago by anonymous
And software-based analogue capture cards are becoming less common, antiquated tech ...
Actually that's an understatement, they were surpassed by hardware capture cards years ago.
comment:12 Changed 4 years ago by anonymous
Maybe so, but I have such a card and I'm not afraid to use it. ;)
I'm compiling svn+patch now, to test it.
comment:13 Changed 4 years ago by anonymous
Been using the patch for a while now and it seems to work.
Changed 4 years ago by Alan Calvert <cal@…>
- Attachment 3405-v6.patch.gz added
refresh @ 20846, lightly tested.
comment:14 Changed 4 years ago by janne
- Status changed from accepted to closed
- Resolution set to fixed
(In [21448]) adds alsa audio input to analog cards. Fixes #3405
factors the audio device handling code out of NuppelVideoRecorder? into a AudioInput? class with OSS and new ALSA implementation.
based on patches by: Alan Calvert, Anand K. Mistry and Daniel Kristjansson
Patch for alsa capture