Tuesday, September 28, 2010

printing to USB printer using Command prompt

Found that the way to use the command prompt to print to a USB printer is by sharing it and using the net use command to map it to a printer port. But then, when I did
net use lpt3: \\mymachine\shared_name /persistent:yes
it gave me the error message
The local device name has a remembered connection to another network resource.
I tried restarting the machine, but the error still remained. So I just mapped my USB printer to lpt3 instead of trying to fight with Windows.

Sunday, September 26, 2010

printing to centronics printer from USB

All these days, I was printing to the MSP 345 24-pin Epson compatible printer from my laptop over the network, since the laptop did not have a parallel port. Today I tried out a USB-36-pin Centronics cable, so that I can directly print from the laptop which has only USB ports to the parallel port only printer without having to switch on another machine. Installing drivers had to be done manually, and at the point in the Wizard where Windows asks you for the port, you have to choose USB001 (Virtual Printer Port for USB) as given at this page. Then everything works fine.

Tuesday, September 21, 2010

video encoding for viewing on mobile

With the 1 GB storage card, viewing long videos on the Qtek 9100 is now a possibility. It plays low bitrate files just fine, but hiccups for higher res. files since the processor is not powerful. Resizing to 320 x 240, XviD codec at 100 kbps video and mp3 codec at 24 kbps mono for audio looks quite OK. File size at this bitrate is around 1 MB per minute. Can use virtualdubmod with avisynth for video conversion, for example.

Saturday, September 18, 2010

more apps on the Qtek 9100

With the 1 GB memory card in the Qtek 9100 mobile, I can install more and larger apps. Opera Mobile 10 was a success, but it uses a lot of memory and seems to use more network also than the previous version. Nice interface, though, and has tabbed browsing. Had to reset IE as the default browser, since Opera was drinking so much RAM it has to run standalone and takes a long time to open. For that, followed this article to download FixIE.cab (requires registration) from the xda developers forum and run it. Have not tested it yet, hope it works. Google maps was not available from the publicized link at m.google.com/maps - manually downloaded it from www.google.com/mobile/maps/ which had a link to download binary. Skype for Windows Mobile has been discontinued, but I downloaded from CNET. Flopped. Voice quality is as bad as before. Tried iSkoot for Skype. At first it said password is wrong. Some forum pointed out that iSkoot requires only alphanumeric password! Tried that, now the error message changes to "Currently unable to connect." Maybe this is because I'm in India? So, back to Fring. But some problem with installing it, "error opening the shortcut or locating the target filename" - have contacted fring support.

problems with Seagate portable external drive

The Seagate portable 2.5 inch 500 GB external USB drive started having problems with reading. Would read 1 GB or so, and then stop. On Windows, it would give "unable to read" error, while on Linux the reading speed would slow down to a trickle before starting up again after a minute. Opened it up using tips for similar drives from instructables and ifixit breaking the plastic tabs on the enclosure in the process :(
Opening the screws on the sides of the metal frame took two of us - one to push down the star screwdriver, and the other to rotate it with the help of pliers - it was so tight. Once the drive came out, connected it to a USB-Sata-Pata adapter by borrowing Sata cable from saispace2. Now the drive reads fine.

Friday, September 10, 2010

FX with Reaper

Explored some of the audio effects bundled with Reaper. Very nice. For example, ReaFir in subtract mode, does noise reduction on the fly! So, I could remove noise and record a clean signal for the keyboard even though the signal going to the PA system had lots of hum! ReaVerberate is the FX to use for a reverb-like effect for live mixes - I reduced the Wet signal to -10dB in the Live Vocal preset and used that. ReaVerb introduces a lot of delay - probably that is useful only for offline work. The JS: LOSER/masterLimiter appears to do a good job in making the output LOUD without distorting - useful for broadcast if not using external compressor hardware.

a caveat for audio routing with the Tascam US-1641

While setting up for recording with Reaper, I'd set up outputs 3&4 on the Tascam US-1641 as the channels to send to digital out, which is what I record. 1&2 are being used as headphone monitors, on which I can do Solo etc. Found that on restarting the machine, the digital outputs again go back to 1&2 by default. If the machine is put in hibernation, this does not happen. So, only if the machine is restarted, I have to go to the Tascam control panel and change the digital outs to 3&4.

Thursday, September 09, 2010

Image albums on portable devices - ebooks

To show some pictures from facebook and picasa to A, tried different techniques. One way was to just save jpgs on the phone and show it using the phone's image viewer. This is slow for many pictures and doesn't include captions. Exporting pdf from Picasa was neat, included captions also (configurable). This was using Picasa3
File -> Print after selecting the required photos. I chose paper size as 'screen' and it was quite good for viewing on phone. In the print dialog, there are options for including captions etc.

For Facebook pix, I tried the Librie toolbar which saves an LRF file. Reasonably OK, except that there will be 5-6 pages of cruft between images while viewing on the Sony ebook reader.

Copy-pasting images into google docs and exporting as pdf did not work for some reason - the images were not being seen on the mobile's Clearvue pdf reader, though the desktop pdf software shows the images. Another failed experiment was exporting to epub from RTF file etc using calibre. The epub file had all the images in one page, squashed together in thumbnail size.

Copy-pasting into Microsoft Word and printing as pdf did work, though the output was not as clean as with Picasa - the page size setting was not perfect, and resizing of images to fit the page size is not automatic.

So, maybe the best option is to save images to a folder and export them from Picasa as PDF.

Radiosai listener stats

B wanted listenership statistics for the Radio Sai Global Harmony streams. We have stats on total number of visitors served and total number of GB served. Dividing GB by no. of visitors, we arrive at GB/visitor which can be translated into no. of hours per visitor since our streams are approx 10 MB per hour. Eg. July to Dec 2009,
Data transferred - 5.63 terabytes.
Distinct hosts served - 157,032.
Average - 5.63 x 1024 x 1024 / 157032 = 37.6 MB per host,
around 3.7 hours per visitor.

Another derived metric - Total data served divided by the time period of the stats gives us average number of simultaneous listeners. We can take 250 MB as data transferred for one listener per day. Once again, in July to Dec 2009,
Data transferred - 5.63 terabytes.
Data is for - 185 days.
Average - 5.63 x 1024 x 1024 / (185 x 250 ) = 128,
around 128 simultaneous listeners on an average.

This figure has been going up steadily over the years:

adventures with tgawarper

To go forward with the mirrordome project, purchased the tgawarper software for windows from LochNess. It appears to have some bugs, as the product page itself notes -
When using the "-o output filemask" option and the filemask contains a folder
structure or drive letter, the program will prepend its "w_" onto the filemask
instead of the actual filename — instead of creating "d:/output/w_filename.tga",
it will create "w_d:/output/filename.tga" (which will likely fail). So you may
have to be creative in order to use this feature in its current implementation.

My workaround was to copy the exe to the folder which had the input images, and run it from there without the -o option, so that output also goes to the same folder.

Time taken: for
tgawarper -w 1920 -a 5 s3_%04d.tga EP_xyuv_1920.map
it took approx 2.9 seconds per frame on my Athlon X2 Dual Core @ 1.9 GHz. 36 seconds of 30 fps video, 1100 frames in an hour. Later, using Virtualdub and AVISynth to make a 6 Mbps HD movie using XVid codec, approx 2.5 fps rendering speed. The AVISynth input avs file was using ImageSource, an avs file with the following lines:
video = ImageSource("w_s3_%04d.tga", 0000, 1110, 29.97)
audio = DirectShowSource("C:\My Path\myfilename.mov")
return AudioDub(video, audio)

phone recording - good only for voice memos

Tried recording on the QTEK 9100 at 44.1 kHz 16 bit mono using the built-in mic. Saturates pretty badly for the volume levels inside bhajan hall during bhajans. Also has a rolloff at 8 khz. 30 ms lag in 30 minutes compared to the Tascam recording.

extracting video recorded on DVD - isobuster

DS had some DVDs with video which were not readable. Apparently they had been recorded with a Toshiba DVD Video recorder DVR17. The DVDs were written, but not finalized, and the session was left open according to Nero. Nero was unable to finalize it because the format is slightly different, since it was written by a hardware DVD player. I tried to get a raw dump of the data using dvdisaster, did not work - dvdisaster needs ECC data from a 'good version' of the disk to start with, I suppose. Then tried the free version of isobuster. It showed the VOB files, but required us to buy the software to extract them. DS ponied up the $30 and we got the files out.