Transcript Automated HDR Image Capturing System

Automated HDR Image
Capturing System
Angela Buttrick, Nate Naber, John
Olender
Agenda
Project Overview
System Description
User Interface
Operating Boundaries
Feasibility/Potential Problems
Test Strategy
Project Overview
HDR image – capture a much wider dynamic
range of intensities than a regular LDR image
Project Overview
1. Remote Control Unit
(RCU) takes pictures
2. Pictures are then
uploaded to the PC
3. Software package then
handles extracting
images and converting
each series of pictures
into HDR images
4. These HDR images run
through an algorithm to
produce a final picture
System Description - Camera
Megapixels
High Resolution 3.2 Megapixel CCD
Focal Length
5.4 - 10.8mm, f/2.8 - 3.9 zoom lens (35mm film equivalent: 35 - 70mm)
Digital Zoom
3.2x Digital Zoom (Max 6.4x digital zoom when combined with optical
zoom)
Maximum Aperture
/2.8/ 7.1 (W), f/3.9/ 10 (T)
Shutter Speed
15 - 1/1,500 sec.
ISO Sensitivity
Auto/ ISO 50/ 100/ 200/ 400
Image Compression
Still Image: JPEG (Exif 2.2 compliant)
System Description - RCU
Remote Control Unit (RCU):
– HCS12 microcontroller
– USB host controller
– Buttons/LEDs for control and
system status
– Battery four AA rechargeable
batteries used to power all
contained components.
Ready
START
-
Battery Pack
4 AA DuraCell
~4.8 Volts, 1800mAh
+
STOP
ON/OFF
text
Running
Error
Remote Control with
HCS12uC
– RCU will include a standardsize Type-A female USB
port, provided by the USB
host controller
System Description – USB Host
Controller
MCU-to-USB host
controller module,
specifically designed for
adding USB host
functionality to
microcontrollers
Allows the camera to
recognize the RCU as a
USB host
Makes the USB protocol
transparent to the HCS12
FTDI VNC1L MCU to USB Host
Controller (VDIP1 Module)
VDIP1 Schematic
System Description – PTP
Picture Transfer Protocol (PTP) – used for
communication between HCS12<->Canon
Camera
Canon cameras use a series of command
and response blocks to send packets back
and forth
PTP Send / Receive Packets
0000000: xx xx xx xx yy yy yy yy - 00 00 00 00 00 00 00 00
0000010: 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00
0000020: 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00
0000030: 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00
0000040: 02 00 00 00 UU 00 cc VV - xx xx xx xx SS SS SS SS
0000050: ... (payload/arguments)
0000000: 00 00 00 00 yy yy 00 00 00 00 00 00 00 00 00 00
0000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000040: 02 00 00 00 UU 00 cc VV - xx xx xx xx SS SS SS SS
0000050: kk kk kk kk
System Description – HDR
Software Packages
Pfscalibration: allows for the calibration of the camera
used to take the pictures and the recovery of HDR
images from the multiple exposure images collected
using the RCU
Pfstools: provides a set of tools for reading and writing
HDR images. This will allow for the storage and
previewing of raw HDR images
Pfstmo: allows for tone-mapping operators to be applied
to HDR images, producing images which may be
displayed on a LDR display device
contains the gradient domain compression scheme
tone mapping operators
Pfstmo Examples
Mantuik '06 Tone Mapping Operator
Fattal '02 Tone Mapping Operator
User Interface
• Clean, easy-to-use UI
– Allows user to calibrate
his/her camera for optimal
HDR images
– Allows user to select a
range of images to be
processed
– Converts LDR->HDR
image by invoking pfstools,
pfscalibration, and pfstmo
– Displays resulting image to
the user
Operational Boundaries
Limiting Factors
– Portability – Camera can only extend up to 3 meters from the
RCU
– Image Quality – Necessary to have stable Camera and still
image
– Power – Limited by battery power, batteries increases portability
Four AA batteries can supply ~4.8V. 1800mAh to each component in
the RCU requiring power
Typical operating conditions:
–
–
–
–
–
–
LEDs draw 12mA (one LED lit)
Buttons draw 12mA
HCS12 microcontroller draw about 100mA
VNC1L USB host controller draw about 25mA
Total current draw of 149mA
~12 hours of use with constant use
Battery condition and temperature
Analytical Component
Time for HDR Automated Flow:
– Experimentation to derive time to save image to flash,
shutter speed’s effect on capture time
Number of photos taken per HDR
– Experimentation of the optimal number to produce
best image
– Affects total memory available
– Max # of photos is Dictated by mega pixel
size/memory card size
Analytical Component
Why do we need so many exposures?
Range of exposures too narrow
(missing very light / very dark
information from the scene)
Not enough exposures to cover the
range (light/dark details in the scene
emphasized too highly)
Feasibility/Potential Problems
• Controlling shutter speeds via the RCU
• PTP/IP and Canon PTP
• User Interface:
• Compiling set of images into a single HDR image
• Completely transparent to the user
• Invoking processes through a GUI and piping I/O quietly
• Open-source software tools with the software UI
• Drop-in USB Host Controller
• Battery Power
• Low-power circuitry as well as low-power modes
• WAIT and STOP power-saving modes of HCS12
Testing Strategies – UI/Software

UI needs to start up properly + allow user to select a
number of images only

Camera calibration function must be tested with the
ability to load/save camera calibration info

Image processing must be tested with a list of images
loaded and camera successfully calibrated

Fail-over testing will be performed in depth in order to
prevent a number of user errors from occurring
Testing Strategies - RCU
 Setup
 Layout Physical Connections
 Establish/Verify Canon Capture
 Phase 1
 Verify Camera is recognized by PC
 Establish/Verify Canon Capture camera connection to PC
 Send simple instruction to Camera, i.e. Zoom 2X
 Check for completion
 Send shutter control from PC
 Take pictures at various shutter speeds
 Remove/Download/Verify Images used different shutter speeds
 Phase 2 – Same as Phase 1 but with the HCS12 instead of the PC
 Phase 3
 Verify Buttons properly send instructions to the Camera
 Verify LEDs show correct status during HDR capturing
Questions?