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happiness 		 808 Car Keys Micro Camera Review
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GumPack Camera

The gumpack camera electronics are similar to the 808 car keys micro camera.
I don't review the gumpack.  It has many versions.


  
2010 Aug 30 - GumPack - Removing the Time Stamp and External USB Power Supply
Isoprop from Switzerland has made a some great mods to his gumpack camera (the gumpack is like the 808 #3).

For the simplest project, which makes it possible to use an external USB battery pack, I think I was extremely lucky to find the correct track to cut. I do realize that this is very specific to the GumPacks and the actual model design. I believe that almost anyone is capable of cutting the track. It's certainly worth the effort.

In a nutshell, the two projects cover how to reprogram the SPI memory to get rid of the timestamp (should work on all SunPlus cameras) and how to record continuous video for about 7 hours (GumPack and model specific).

My two projects are here:

GumPack Removing the Time StampHow to remove the time stamp on the GumPack #3 camera
http://www.mytempfiles.info/gum/project1.html












GumPack External USB Power SupplyAdding an external USB power supply
http://www.mytempfiles.info/gum/project2.html

  
2010 June 18 - GumPack Camera with Dual Resolution
Alex bought a gumpack camera (similar to a #5 camera) that has both 640x480 and 720x480 video resolution.  He figured out how to toggle between the resolutions (not documented).

Conclusion:  It's better to take videos at 640x480, as frame rate is higher and it captures more detail.

==========

This gumpack camera has a Syntek processor, a white video date time stamp in the lower right corner, takes a micro SD card, and has 64Kbps audio.  So the electronics are similar to a #5 808 camera.

The camera documentation claims a video resolution of 720x480 and 1280x1024, and a photo resolution of 1600x1200 and 3264x2448.  The instructions sheet does not describe how to toggle between resolutions.  Through some trial-and-error and intuition, Alex was able to discover a button pressing sequence to switch the resolution. 

The two video resolutions discovered are 640x480 and 720x480 (different than documented).  Also, a big surprise:  There is no aspect ratio (AR) distortion in both video resolutions.  The photo JPG resolution does not change from 1600x1200 with timestamp always 30px high.

The AVI MJPG video was initially 640x480.  To toggle between 640x480 and 720x480:
1. Turn the switch to ON.
2. Press the record/stop button and hold it: the green light will turn on, followed by the blue one, then the red one will flash once and all lights will go off (entire cycle takes about 10s).
3. Release the record/stop button.

Video FPS:  640x480 29.774,  720x480 28.918.

Alex took a video of a CD (a circle object) at both resolutions, keeping the camera exactly in the same position, and it turned out that the video at 720x480 is zoomed-in compared to the one at 640x480.

Here is what Alex thinks the camera does to create a 720x480 video:
- capture a frame at 640x480 (native CMOS resolution)
- resize to 640x540 (image is distorted, CD is elongated vertically)
- crop 60px at the bottom and get a 640x480 frame (image is still distorted)
- add the timestamp
- resize at 720x480 (image is no longer distorted, timestamp is stretched)

Note that, in all AVIs and JPGs, there is no aspect ratio distortion and the date time stamp is always 30 pixels high.
Gumpack
GumPack AVI video frame, original 640x320		 Gumpack
GumPack AVI video frame, original 720x480. 
Effectively a zoomed in and scaled part of the 640x480 video.
The date time stamp is stretched horizontally, not vertically.
Gumpack
GumPack JPG photo, original 1600x1200		  

  
2010 Feb 12 - Hacking the Gumpack Camera (like the #3 Camera)
gumpack camera gumpack camera teardown gumpack camera teardown

At Philippe's website there are more images, the raw dump file, and much more information:

Philippe from France has done some great hacking of his gumpack camera, with the intent of modifying the software to remove the video date time stamp.  The gumpack has the same characteristics (720x480, 30FPS) as the #3 Camera.  Once connected as a mass storage device (hardware ID 04FC 0171), a short press of the power button will put the camera into webcam mode (hardware ID 04FC 1528) if the SPCA1528 webcam driver is installed.

Like the #2, #3 and #4 cameras, this  gumpack has an 8 pin serial flash chip.  This chip is 2 megabytes.  I speculate that it contains part of the camera software, loaded into RAM at boot time..  Philippe removed the 2 megabyte chip and dumped the memory to a file, and has been analyzing it.  Surprisingly there are 16 JPG images embedded in the flash (see his site).

Philippe has determined from the dump that the processor is not an ARM processor but is a clone of a 6502 processor (like used in the Apple I, Apple II and the Commodore 64 computers).  So, maybe using a 6502 disassembler will reveal some code.

Here is an example of some strings in the raw file, as displayed by the free HxD Hex Editor

00093B20  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................................
00093B40  09 7B 30 78 30 62 2C 20 22 53 74 72 69 6E 67 2E 73 73 74 22 2C 20 30 78 30 30 2C 20 30 78 35 30  .{0x0b, "String.sst", 0x00, 0x50
00093B60  30 30 7D 2C 55 53 42 5F 56 45 4E 44 4F 52 5F 49 44 20 3D 20 22 30 78 30 34 46 43 22 0D 0A 55 53  00},USB_VENDOR_ID = "0x04FC"..US
00093B80  42 5F 50 43 43 41 4D 5F 50 52 4F 44 55 43 54 5F 49 44 20 3D 20 22 30 78 31 35 32 38 22 0D 0A 55  B_PCCAM_PRODUCT_ID = "0x1528"..U
00093BA0  53 42 5F 4D 53 44 43 5F 50 52 4F 44 55 43 54 5F 49 44 20 3D 20 22 30 78 30 31 37 31 22 0D 0A 55  SB_MSDC_PRODUCT_ID = "0x0171"..U
00093BC0  53 42 5F 53 49 44 43 5F 50 52 4F 44 55 43 54 5F 49 44 20 3D 20 22 30 78 30 31 37 32 22 0D 0A 55  SB_SIDC_PRODUCT_ID = "0x0172"..U
00093BE0  53 42 5F 4D 41 4E 55 46 41 43 54 55 52 45 52 5F 4E 41 4D 45 20 3D 20 22 53 75 6E 70 6C 75 73 20  SB_MANUFACTURER_NAME = "Sunplus
00093C00  43 6F 20 4C 74 64 20 22 0D 0A 55 53 42 5F 50 52 4F 44 55 43 54 5F 4E 41 4D 45 20 3D 20 22 47 65  Co Ltd "..USB_PRODUCT_NAME = "Ge
00093C20  6E 65 72 61 6C 20 49 6D 61 67 65 20 44 65 76 69 63 65 22 0D 0A 55 53 42 5F 53 45 52 49 41 4C 5F  neral Image Device"..USB_SERIAL_
00093C40  4E 55 4D 42 45 52 20 3D 20 22 30 31 2E 30 30 2E 30 30 22 0D 0A 4D 53 44 43 5F 56 45 4E 44 4F 52  NUMBER = "01.00.00"..MSDC_VENDOR
00093C60  5F 49 44 20 3D 20 22 22 0D 0A 4D 53 44 43 5F 50 52 4F 44 55 43 54 5F 49 44 20 3D 20 22 47 65 6E  _ID = ""..MSDC_PRODUCT_ID = "Gen
00093C80  65 72 61 6C 22 0D 0A 4D 53 44 43 5F 52 45 56 49 53 49 4F 4E 5F 49 44 20 3D 20 22 31 2E 30 30 22  eral"..MSDC_REVISION_ID = "1.00"
00093CA0  0D 0A 53 49 44 43 5F 4D 41 4E 55 46 41 43 54 55 52 45 52 20 3D 20 22 53 75 6E 70 6C 75 73 6D 6D  ..SIDC_MANUFACTURER = "Sunplusmm
00093CC0  22 0D 0A 53 49 44 43 5F 4D 4F 44 45 4C 20 3D 20 22 47 65 6E 65 72 61 6C 22 0D 0A 53 49 44 43 5F  "..SIDC_MODEL = "General"..SIDC_
00093CE0  44 45 56 49 43 45 5F 56 45 52 53 49 4F 4E 20 3D 20 22 30 31 2E 30 30 20 22 0D 0A 53 49 44 43 5F  DEVICE_VERSION = "01.00 "..SIDC_
00093D00  53 45 52 49 41 4C 4E 55 4D 42 45 52 20 3D 20 22 30 30 20 20 20 20 20 20 22 0D 0A 53 49 44 43 5F  SERIALNUMBER = "00      "..SIDC_
00093D20  56 45 4E 44 4F 52 45 58 54 5F 44 45 53 43 20 3D 20 22 53 75 6E 70 6C 75 73 6D 6D 22 0D 0A 0D 0A  VENDOREXT_DESC = "Sunplusmm"....
00093D40  0D 0A FF D8 FF E0 00 10 4A 46 49 46 00 01 01 01 00 60 00 60 00 00 FF DB 00 43 00 08 06 06 07 06  ..ÿØÿà..JFIF.....`.`..ÿÛ.C......
00093D60  05 08 07 07 07 09 09 08 0A 0C 14 0D 0C 0B 0B 0C 19 12 13 0F 14 1D 1A 1F 1E 1D 1A 1C 1C 20 24 2E  ............................. $.

Philippe also measured current consumption in the gumpack camera.  "I measured the battery capacity at 270mAh (discharge current of 200mA, down to 3.0V). So I expect it to be able to last a bit more that one hour".

Current mA Switch Description
zero Off This gumpack camera does not have a reset button.  Off disconnects the battery.
0.02 On Sleep
115 On Green LED on.  The current waveform shows a frequency around 15 KHz, hello RTC clock !
145 On During video recording.  There are some spikes at 220 mA every 64ms. It’s probably when the SD card is written.



  
2010 XXX XX - XXXXXXXX
 
   

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