Writing an ALSA Renderer for Linux

Hi,
I want to write an ALSA Renderer for Linux because I have problems with the JavaSoundRenderer in Linux and I really need a fast Audio Renderer for my app.
What I need is a short tutorial for ALSA that shows how I can play sound with it.
If you know a good tutorial or if anyone can give me short instructions for dealing with this problem post it here please.
Best regards, thomas

Have you looked at OSS ??
I did some open sound system on linux, and it was easy.
Lots of documentation/examples.
I also used the exact same code, but compiled a dll on a linux box, to use on windows, with JNI, and it worked.
Check out OSS if you haven't yet.
http://www.opensound.com/linux.html

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Writing a custom renderer for the component "af:processTrain" in 10g

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I have a requirement where we need to customize the way the af:processTrain is rendered. For this, the simpler and the more generic way would be to write a custom renderer for the af:processTrain component. Is there any documentation or examples that could help in accomplishing this as I could not get any relevant examples or documents.
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Swapna

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Thanks for the quick response. Could you please suggest me a way to go about writing your own custom renderers?
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New Skype for Linux released, version 4.3 | Edit: Now in Repo's

A New Skype has been released for Linux. Not quite yet in our repo's as of this writing. Skype 4.3 is now in the official repo's.
One of the larger changes is that ALSA is no longer supported and users are instead directed to use Pulse Audio. I already use Pulse, but I can imagine there will be some people unimpressed with this new requirement.
Unfortunately when it comes to network messaging programs the protocol is what rules. All my friends use the Skype protocol so I also have to use it to communicate with them. As far as I'm aware there is no full-featured replacement for the Skype protocol on Linux that also does audio and video.
What do you think?
Note: I posted in Multimedia, if there is a better place for this please feel free to move it. Perhaps networking, but Skype is a multimedia/network application.
Last edited by headkase (2014-06-21 16:55:13)

ninian wrote:
drcouzelis wrote:
There is one more option to consider, though, one that I find fascinating: WebRTC. WebRTC is native voice and video chat in a web browser. Both Firefox and Chrome have supported it for some time now, so if you and your friend use one of those web browsers then you don't need to install any special software. Just send them a link to a web page and start using it.
Disclaimer: I tried it about a year ago. Firefox was able to display my webcam video but I never successfully established a connection with my friend. I should try it out again...
I tried it out a few weeks ago on a couple of computers running Arch, and managed to get it working fine between all combinations of Chromium and Firefox (all up to date, mind). I used Talky and it certainly made WebRTC easy. I just need to convince members of the family to stuff Skype now!
Thanks so much for the Talky suggestion.
I tried to convince people to use Jitsi and register for their Jabber service, but unfortunately a lot are content with using Skype.

[SOLVED] Lousy fonts with .chm viewer for Linux

I installed the .chm file viewer HelpExplorer 3.0 in both Windows XP and Arch Linux (chm = compiled HTML help file). In Windows XP, with default fonts installed, the fonts in text read with this viewer appear crisp, sharp and anti-aliased. In Arch with KDE 3.5.7, on the other hand, the fonts appear fuzzy, grainy and don't seem to be anti-aliased, in contrast with their appearance in all other apps (except for a few such as Dillo) which render text good-looking, sharp and anti-aliased.
HelpExplorer for Linux was provided as a tarball that included a precompiled 'helpexplorer' binary. The program doesn't seem to allow for customizing font settings.
The following fonts are installed in Arch (in /usr/share/fonts/):
ttf-bitstream-vera-1.10-5 is installed by default
gsfonts 8.11-4 is installed by default
PostScript Type 1 fonts installed: Century Schoolbook, Nimbus, URW Bookman, URW Gothic, URW Palladio
ttf-ms-fonts-2.0-1 (Microsoft TTF: Andale Mono, Arial, Comic, Courier, Georgia, Impact, Tahoma, Times New Roman, Trebuchet)
font-bh-ttf-1.0.0-3 (Luxi BH)
xorg-fonts-100dpi-1.0.1-1 (courier, helvetica, lucida, new century, times)
The "Files" section of my xorg.conf looks as follows:
Section "Files"
RgbPath "/usr/share/X11/rgb"
ModulePath "/usr/lib/xorg/modules"
FontPath "/usr/share/fonts/misc:unscaled"
FontPath "/usr/share/fonts/misc"
FontPath "/usr/share/fonts/75dpi:unscaled"
FontPath "/usr/share/fonts/75dpi"
FontPath "/usr/share/fonts/100dpi:unscaled"
FontPath "/usr/share/fonts/100dpi"
FontPath "/usr/share/fonts/PEX"
# Additional fonts: Locale, Gimp, TTF...
FontPath "/usr/share/fonts/cyrillic"
# FontPath "/usr/share/lib/X11/fonts/latin2/75dpi"
# FontPath "/usr/share/lib/X11/fonts/latin2/100dpi"
# True type and type1 fonts are also handled via xftlib, see /etc/X11/XftConfig!
FontPath "/usr/share/fonts/Type1"
FontPath "/usr/share/fonts/ttf/western"
FontPath "/usr/share/fonts/ttf/decoratives"
FontPath "/usr/share/fonts/truetype"
FontPath "/usr/share/fonts/truetype/openoffice"
FontPath "/usr/share/fonts/truetype/ttf-bitstream-vera"
FontPath "/usr/share/fonts/latex-ttf-fonts"
FontPath "/usr/share/fonts/defoma/CID"
FontPath "/usr/share/fonts/defoma/TrueType"
EndSection
I've attached a screenshot of some text displayed in the HelpExplorer reader in Arch (the font is Times New Roman): http://img216.imageshack.us/my.php?imag … ot1zh9.png
[img=http://img216.imageshack.us/img216/8401/snapshot1zh9.th.png]
What do I need to do to improve the font appearance in this program in Linux?
Last edited by RobF (2007-10-02 18:06:46)

I found a solution of sorts by installing and running the Windows version of HelpExplorer in Wine or Crossover. There is still very little control over fonts but when I enlarge the default font (with 2x CTRL-+) I do get a nice-looking anti-aliased Times New Roman font, and this solution would be my preferred way of reading .chm files in Linux (i.e. better than KchmViewer or Xchm).
Recap of the problem:
1. The .chm viewer HelpExplorer Viewer 3.0 when installed in Windows XP renders fonts crisp and clear and anti-aliased.
2. The Linux version of HelpExplorer Viewer 3.0 (delivered as a precompiled executable in a tarball) doesn't render fonts antialiased, regardless of what I tried, and they look grainy and unattractive.
3. The Windows version of HelpExplorer Viewer 3.0 when installed and run in Arch in Wine or Crossover does render the default font they offer (looks like Times New Roman) fairly crisp and clear and anti-aliased, at least at the enlarged setting.
Can someone explain to me what might be going on? Why is it that the Linux version cannot render fonts anti-aliased when the Windows version running in the emulator in Linux can? Is there something that I have to change in my fonts config, fonts location, symlinks or path to get the anti-aliased fonts to work in HelpExplorer in Linux?
Robert

How to create a c++ shared library (.so) for linux real time (for myRio) with Eclipse to use in LabView?

I tried already these Tutorials and Advices but I didn't find a solution:
- http://www.ni.com/tutorial/14625/en/
- http://www.ni.com/tutorial/14690/en/
- http://forums.ni.com/t5/LabVIEW/Shared-Library-on-myrio-Linux-Real-time-system/m-p/2842540/
- http://forums.ni.com/t5/LabVIEW/How-to-create-shared-library-for-linux-real-time-target-in/m-p/28218...
- and some more
I want use c++ codes on linux real time. For testing reasons I want to have a function that adds 2 values and gives the result.
I've done these steps:
1. writing a c++ file in Eclipse (see screensot 2)
2. building a shared library (.so) from my c++ project in Eclipse (with Cross GCC)
3. putting this file on myRio (path: /usr/local/lib/)
4. creating a VI that calls this library from Labview with a "Call Library Function Node" (see screenshot3)
5. Setting the properties for the "Call Library Function Node" (see screenshots 4-7)
After I run this VI i get this error message: LabVIEW: (Hex 0x627) The function name for the ... node cannot be found in the library. To correct this error, right-click the Call Library Function Node and select Configure from the shortcut menu. Then choose the correct function name. (see screenshot1)
I've tried a lot things to solve this problem but I couldn't find a solution. Would be very happy if anyone can help me. I guess that I have to edit my c++ code to export my function (symbol). But I have no idea how to make it. I also tried it with a dll file in the same folder but it didn't help.
Perhaps someone can send an example which works on myRIO.
Thanks!
screenshot1
screenshot2
screenshot3
screenshot4
screenshot5
screenshot6
screenshot7

can see it in the screenshot8 there is a function called "_Z8AddierenddPd" instead of "Addieren". I copied this name to Labview (see screenshot9) and it worked.
I'm sure that there is a way to compile the shared folder with gcc without decorations (mangling). But I don't know how. If someone has a recommendation I would be very glad!
Prepend each function declaration that you want to be available without name decoration with
extern "C" <your function declaration>
Or if you have multiple functions you want to export you can in the header file where you declare your functions simply use:
#ifdef __cplusplus
extern "C" {
#endif
<all your function declarations>
#ifdef __cplusplus
#endif
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

Not working Webutil configuration for linux

I had configured webutil in linux server as per document. my basic cofiguration is
OS - Linux redhad(4.0)
Front End - Forms [32 Bit] Version 10.1.2.0.2
Now i had created form in that form i m using webutil when on test button i m calling
show_webutil_information (TRUE);
It is showing all the webutil information
But on another button i m calling
v_ole_excel := client_ole2.create_obj ('Excel.Application');
client_ole2.set_property (v_ole_excel, 'visible', 1);
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So Please Guide us to resolve the problem.
Thank's in anticipation,
Regards,
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Loading TUI files in Linux it's an issue that we have recently discovered and it did not made it yet to the known issue list. I'm not 100% sure but I believe a workaround to that problem would be to go and manually edit that tui file and remove those attributes that generates errors. You can begin with ATTR_TITLEBAR_STYLE and then look if one of the following are in the tui file: ATTR_DS_BIND_PLOT_STYLE, ATTR_DS_BIND_POINT_STYLE, ATTR_DS_BIND_LINE_STYLE, ATTR_DS_BIND_PLOT_COLOR and delete them. Then try to load the tui file again.
On the other hand I think there is a workaround for your original problem: the predefined fonts (VAL_DIALOG_METAFONT) looks bad on Linux. I believe there is a way a user can change the underlying font and the size of a predefined font. In windows you can change it in the registry but in Linux you can define an environment variable: XAPPLRESDIR that points to a directory that should contain a file named cvi, a file where you can write font settings. Each line has to be of the following format: <appName>.<key>:<value>. If you want the settings you're writing to be persistent for all applications the put a "*"instead of the application name.
The list of possible key is: appFont (NIAppMetaFont), menuFont (NIMenuMetaFont), dialogFont (NIDialogMetaFont), editorFont (NIEditorMetaFont), messageBoxFont (NIMessageBoxMetaFont).
The value have to be of the following form: --
Here is the only line I have in the cvi file: *.dialogFont : adobe-helvetica-19

Load panel tui file not working on CVI2012 for Linux

We are having problems with panels that look fine on Windows being difficult to read on Linux, presumably because most control and text fonts are VAL_DIALOG_META_FONT on Windows but the CVI for Linux run-time only has NISYSTEM.
As a quick way to test different fonts on Linux I created a tui file from the uir file and then used global search and replace to change VAL_DIALOG_META_FONT to something that would hopefully look decent on Linux.
Problem is that LoadPanel(0,"filename.tui",1) works on WIndows but throws error -46 on Linux.
Whereas LoadPanel,0,"filename.uir,PANEL) works fine on Linux & Windows but the fonts are very hard to read on Linux.
Is there a table somewhere mapping the VAL_FONT attribute magic numbers to corresponding fonts on Windows and Linux?
It'd be nice to have some guidance on the default font mappings. But at the end of the day, I don't really care much about fonts unless the defaults are hard to read.
I guess one other potential complication is the UIR file originally came from CVI 8.5, but CVI 2010 for Windows didn't say anything about needing to "convert" it. Perhaps one of the attributes in the tui file is not valid on Linux, but is on Windows?
Solved!
Go to Solution.

Loading TUI files in Linux it's an issue that we have recently discovered and it did not made it yet to the known issue list. I'm not 100% sure but I believe a workaround to that problem would be to go and manually edit that tui file and remove those attributes that generates errors. You can begin with ATTR_TITLEBAR_STYLE and then look if one of the following are in the tui file: ATTR_DS_BIND_PLOT_STYLE, ATTR_DS_BIND_POINT_STYLE, ATTR_DS_BIND_LINE_STYLE, ATTR_DS_BIND_PLOT_COLOR and delete them. Then try to load the tui file again.
On the other hand I think there is a workaround for your original problem: the predefined fonts (VAL_DIALOG_METAFONT) looks bad on Linux. I believe there is a way a user can change the underlying font and the size of a predefined font. In windows you can change it in the registry but in Linux you can define an environment variable: XAPPLRESDIR that points to a directory that should contain a file named cvi, a file where you can write font settings. Each line has to be of the following format: <appName>.<key>:<value>. If you want the settings you're writing to be persistent for all applications the put a "*"instead of the application name.
The list of possible key is: appFont (NIAppMetaFont), menuFont (NIMenuMetaFont), dialogFont (NIDialogMetaFont), editorFont (NIEditorMetaFont), messageBoxFont (NIMessageBoxMetaFont).
The value have to be of the following form: --
Here is the only line I have in the cvi file: *.dialogFont : adobe-helvetica-19

Custom renderer for radio buttons?

I want to change how radio buttons are rendered (so they aren't all rendered alone in their own table). What would be the best way to do this?
One way would be to create a custom component, tag handler, and renderer (and register them all in faces-config.xml).
But what about using the existing JSF components and just writing my own renderer. Could that work? Would just need to write a renderer and configure faces-config.xml to use the appropriate component-family (for the existing JSF radio button component) and renderer-type (for the existing component tag class for the radio button)�.like this:
<render-kit>
<renderer>
<component-family>javax.faces.SelectOne</component-family>
<renderer-type>javax.faces.Radio</renderer-type>
<renderer-class>my.custom.renderer</renderer-class>
</renderer>
</render-kit>
Could this work?
Thanks.

Could this work?Yes. Why do you doubt it?

Schedule for Java ME SDK 3.0 for Linux?

Hi,
thank you for Java ME, we are using it since many years with on Linux development platform.
Currently we plan to use the Sensor API, which is missing in WTK2.5.2 for Linux.
What are the current plans for Linux?
thanks,
Marcel

Another +1
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Toshiba Assist for Linux OS

Hello!
I started to use Ubuntu OS some time ago and Im wondering if there is a proper version of Toshiba Assist driver for Linux. I looked for it but neither the browser on the drivers' download page nor I can't find it ;| What I want is i.e. the FN button options displayed when I press the button.. OFC they work anyway, but it would be useful :)
P.S. I found out that the 1st control button works in other way in Ubuntu (mutes the sound) while in Win Vista it turns ON/OFF the LEDs' light. Now Im wondering how to make the them highlighted :D The others work well with Banshee player.

hello ,
having installed Ubuntu 8.10 , I am now frantically trying to get the PCI modem working.
All the relevant modem drivers have been downloaded i.e. HSF; HCF; DGC; Riptide and Alsa drivers, but I have not found a way to check that the modem is properly installed and it is certainly not working yet!
I am working on a Laptop P300-17S
Anyone who can give me a hint ?

EAX / 5.1 Surround / Dolby - is there anything for linux?!

Hi all.
I've had a 7.1 Hercules Digifire soundcard for a while now, and it was awesome on Windows for surround sound.
Being into my gaming, and just as into my films, I like using linux for both. The problem is, there seems to be absolutely no support whatsoever for EAX/5.1 surround/Dolby surround/ whatever for linux.
I've searched pretty extensively, but as far as I can tell there is NOTHING at all in the way of surround sound support for linux. Is this correct?
It's annoying having hardware sitting around wasting - if anyone can point me to somewhere helpful regarding linux surround, or give me any info, I'd be much obliged
Thanks a lot.
Thom

Wow, thanks... careful tho, you've got my hopes up
Well, I have alsa running, and I do indeed have options for 'Surround' and some others in alsamixer - but they don't make any difference!
I'm not sure if it's my soundcard (I've had issues with microphone - it works, i.e. you can hear yourself in the speakers, but I can't actually record anything?? Set various things to 'Capture' etc, no luck), but seeing as all was well in Windows (while ago now, heh) I tend towards thinking it's a software problem.
Are there any special measures I have to take regarding Alsa and surround sound? I've just got the stock Arch Alsa install, haven't changed anything.
I'll go check the Wiki now. Is it just Creative cards that work? My Alsa module is cs46xx I think - Crystal Fusion. That's different to the Creative cards, right?
Cheers,
T

JDeveloper 11g for linux.

I saw packages for windows and mac, the Base Install is for linux?

it's ...i don't know... a rendering problem...
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best regards...
Message was edited by:
kquizak

Suggestions for Flex Builder for Linux

I'm new to Flex, and I have to say that I'm enjoying it quite
a lot. I think the thing that really helps speed up development is
good tools. Flex Builder 3 for Linux makes a good start at
providing a very nice development tool, but there are a couple of
things I'd like to see different with this tool.
First off, please give me an update site to use to install
Flex Builder. I use Red Hat Developer Studio (soon to be JBoss
Developer Studio, Eclipse 3.2 based), and I can't get FB 3 Alpha
for Linux to install into it. I have been successful with base
Eclipse Europa and FB 3, but I'd like to have my IDE tools in one
frame. An update site would let me add FB 3 into any Eclipse flavor
I choose, as long as it supported the appropriate components.
Next, Design mode for FB 3 is a must. I am very functional
with the content assist features in the source editor (and they are
_quite_ good, I must say), but design view really helps me preview
changes quickly and rapidly test out UI designs. Much faster than
writing and launching over and over.
Otherwise, great work, and please get out a new release
soon!

cdelashm wrote:
> I'm new to Flex, and I have to say that I'm enjoying it
quite a lot. I think
> the thing that really helps speed up development is good
tools. Flex Builder 3
> for Linux makes a good start at providing a very nice
development tool, but
> there are a couple of things I'd like to see different
with this tool.
>
> First off, please give me an update site to use to
install Flex Builder. I
> use Red Hat Developer Studio (soon to be JBoss Developer
Studio, Eclipse 3.2
> based), and I can't get FB 3 Alpha for Linux to install
into it. I have been
> successful with base Eclipse Europa and FB 3, but I'd
like to have my IDE tools
> in one frame. An update site would let me add FB 3 into
any Eclipse flavor I
> choose, as long as it supported the appropriate
components.
>
> Next, Design mode for FB 3 is a must. I am very
functional with the content
> assist features in the source editor (and they are
_quite_ good, I must say),
> but design view really helps me preview changes quickly
and rapidly test out UI
> designs. Much faster than writing and launching over and
over.
>
> Otherwise, great work, and please get out a new release
soon!
>
>
Thank you for your valuable feedback. Can you please take 2
minutes to
log an Enhancement Bug in the bug base so we can track your
request and
work on it as we proceed.
http://bugs.adobe.com/jira
(Choose Flex Builder Linux Project)
Thanks
Arun

How to write a renderer for UIData or its subclass?

Hi, I got some trouble with writing a renderer for UIData or its subclass, can i find the source code of such implementations?I downloaded MyFaces, but I couldn't find the source code for the renderer of UIData ,please help:)
Best Regards:)
Robin

I hava found the renderer implementation code,hehe,thanks:)

"Conforming HDV" instead of "Writing Video" while rendering anything

I am having a serious issue with FCP. I am getting the "Conforming HDV" dialog instead of "Writing Video" while rendering anything
Short Project shot @ 720p 30 with a JVC GY-HD100U
1) This gradually started happening more and more.
2) Whenever I try to render anything, even a small crossfade, FCP shows the "Conforming HDV" dialog and proceeds to trash my video. Pieces of the video are repeated or frames are dropped and shots become jerky.
Undo fixes the issue. Replacing the video with the original fixes the issue. But I connot RENDER ANYTHING!
What would you all suggest?
MBP C2D 15 - Dual 1.25 G4 MDD Mac OS X (10.4.8)

Welcome to HDV. I've never had much better luck than this. The way the GOP structure of the mpeg-2 HDV stream works, the I-frames in your media almost never match up with the default GOP structure of the sequence, and you must wait for it to conform everytime you even think about touching it. Changing the render settings might help. If you are still runnning FCP 4.5, you will be plagued with scrambled render files - even if you can get it to show the correct rendered material in the timeline, if you export or encode or output to tape, you'll wind up with different (wrong) renders in the resulting files.
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Hope this helps -
Max Average

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