camera

Streaming Your Webcam w/ Raspberry Pi

Posted by Wolf Paulus on Sep 8, 2012 in Embedded

[Last updated on Feb. 2. 2013 for (2012-12-16-wheezy-raspbian) Kernel Version 3.2.27+]

Three years ago, we bought two small Webcams and since we wanted to used them on Linux and OS X, we went with the UVC and Mac compatible Creative LIVE! CAM Video IM Ultra. This Webcam (Model VF0415) has a high-resolution sensor that lets you take 5.0-megapixel pictures and record videos at up to 1.3-megapixel, supported resolutions include 640×480, 1290×720, and 1280×960. If you like, you can go back and read what I was thinking about the IM Ultra back in 2009. Today, it’s not much used anymore, but may just be the right accessory for an Raspberry Pi.

With the USB Camera attached to the Raspi, lsusb returns something like this:

lsusb

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp.
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 004: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
Bus 001 Device 005: ID 041e:4071 Creative Technology, Ltd

Using the current Raspbian “wheezy” distribution (Kernel 3.2.27+), one can find the following related packages, ready for deployment:

luvcview, a camera viewer for UVC based webcams, which includes an mjpeg decoder and is able to save the video stream as an AVI file.
uvccapture, which can capture an image (JPEG) from a USB webcam at a specified interval

While these might be great tools, mpeg-streamer looks like a more complete, one-stop-shop kind-of solution.

Motorola Atrix vs. HTC ThunderBolt

Posted by Wolf Paulus on Mar 27, 2011 in Hardware

Not even a year ago, I had three of the top Android Phones available for testing, all running Android 2.1 Update-1, and all running on Verizon’s network, and thought it would be fun to run a couple casual benchmarks. The comparison of the three phones (Motorola Droid, HTC Incredible, and Motorola Droid X) that were cool then, can be read here. Over this weekend, I had the chance to take a closer look at two of the current top phones from Motorola and HTC, the Motorola Atrix and the HTC ThunderBolt.

Motorola Droid – 1st Impressions

Posted by Wolf Paulus on Nov 8, 2009 in Hardware

“I would much rather have gone with Master Luke than stay here with you. I don’t know what all this trouble is about, but I’m sure it must be your fault.”

The Motorola droid is probably the first 2nd generation Android phone and after playing the the HTC Hero and Motorola Cliq, I now had the chance to take a much closer look at the Motorola Droid.

Connectivity

There are two sockets on the droid, a standard headphone jack, which surprisingly works well with iPhone ear-buts (i.e. on/off switch mutes the mic.) and a mirco-usb data access and charging socket. While I have plenty of mini-USB cables, I didn’t have a single micro-usb cable; the one the Motorola has included is short and very inflexible.

Display

The 3.7″ WVGA display (480×854 pixels) is impressive but unfortunately Android’s UI is not really build for it, at least not yet. The icons (48×48 pixels) appear to be way too small now.

Keyboard

I understand that Motorola put a lot of time and energy in getting the Cliq’s keyboard right. Unfortunately, nothing of the teams must not have been talking too each other. The droid’s physical keyboard is hardly more useful than its on-screen virtual keyboard and most droid users will not be able to type as fast on the physical keyboards as iPhone users type on the display.

Buttons

The phone has four physical buttons, and four touchscreen buttons just below the display. As one would expect, the physical buttons are the power button which is way too small, tho. A volume rocker, which is on the wrong side (right), and a camera shutter button. The touchscreen buttons the made possible by extending the touchscreen beyond the display and their haptic feedback really rocks.

The 5MP digital camera is probably the weakest part of the Motorola droid, delivering 5 mega-pixel of noise even when used at best lighting conditions. Some unedited iPhone and Moto Droid shots can be found here: http://www.flickr.com/photos/wolfpaulus/sets/72157604509087860/

Conclusion

The Moto droid is most likely the best Android phone currently available and geeks and developers will love it. However, when compared to the iPhone, the droid lacks basic functionally and user-friendliness we are now so accustomed to. If Google really wants to push Android, it needs to continue to develop the basic applications like mail, calendar, etc. to a point where they are at least as good at what Apple includes with the iPhoneOS. Like it or not, the iPhone OS and the included apps are the baseline now and basic everyday Android applications like Mail and Calendar are plain ugly.

Sh!t We Like – The Creative Live! Cam Vid. IM Ultra

Posted by Wolf Paulus on Jul 12, 2009 in Hardware

Originally I was just looking for a decent Webcam for a Linux project, but since almost all computers in my house run OS X, I thought it would be nice to find one that could be use on a MacMini as well. Fortunately, there is a growing list of UVC compatible devices available, some of which have been tested to work on a Mac out-of-the-box, i.e. without the need to install additional drivers.
Considering Linux and Mac compatibility, pixel/resolution, as well as price, we picked the Creative LIVE! CAM Video IM Ultra, which when compared to a built-in iSight cameras seems to create higher quality videos.

Video Recording

While we used the standard 640×480 video format for the recording below, the VF415 Live! Cam Vid. IM Ultra’s native format is Y’CbCr 4:2:2 -yuvy, 1280×960 with Millions of Colors.

Creative LIVE! CAM Video IM Ultra

Format: H.264 640×480 Millions of Colors, AAC, Mono, 44.100 KHz
FPS: 30 frames per second
Data Rate: 1500.24 kbits/s

MacBook built-in iSight Camera

Format: H.264 640×480 Millions of Colors, AAC, Mono, 44.100 KHz
FPS: 30 frames per second
Data Rate: 711.34 kbits/s

Audio Recording

It was a positive surprise, finding out that there is a microphone hidden in the camera’s focus ring. However, the microphone is pretty much useless, at least when used under Mac OS X. We used WireTap Studio to create a fair comparison recording, using the MacBook’s built-in microphone, the Live Cam Ultra’s built-in mic., as well as an external Logitech USB Microphone.

Creative LIVE! CAM Video IM Ultra built-in Microphone:

Logitech AK5370 external USB Microphone:

Overall, we really like the IM Ultra, the image quality is crisp and it attaches easily to a laptop’s lids as well as a much thicker LCD monitors. However, the audio quality really sucks (at least when used on a Mac and you better have another mic on hand). Moreover, expectedly, the camera doesn’t work on a low power USB port.

Tweak, Hack, and Bend Technology @ UCI

Posted by Wolf Paulus on Oct 17, 2006 in Embedded

Later this week, I’ll be at the OCEJUG, Orange County Embedded Java Users’ Group, to give a presentation titled: Innovate – Tweak, Hack, and Bend Technology, showing how a small device, about the size of an iPod Shuffle, but capable of executing Java-Byte-Code, is turned into a Web server. After taking a very close look inside the workings of a digital toy camera, we will connect it to the embedded device, creating a full featured web-cam.
Along the way we may add some more hardware and learn a few things about how CMOS sensors capture image data and how a Bayer-Pattern can be used to decode the sensor data.

The free OCEJUG event takes place on October 19th at the University of California, Irvine (Engineering Tower, Room 331 / ET331), starting at 6:30 PM.

Wolf Paulus

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