Team Slytherin: Difference between revisions
Jump to navigation
Jump to search
Line 123: | Line 123: | ||
*(edgeImage.data + X + Y*originalImage.cols) = 255 - (unsigned char)(SUM); /* make edges black and background white */ | *(edgeImage.data + X + Y*originalImage.cols) = 255 - (unsigned char)(SUM); /* make edges black and background white */ | ||
fwrite( (edgeImage.data + X + Y*originalImage.cols), sizeof(char), 1, bmpOutput); | fwrite( (edgeImage.data + X + Y*originalImage.cols), sizeof(char), 1, bmpOutput); | ||
=== Profiling C code Using gprof === | |||
Compile the c code with -pg option | |||
gcc -pg -lm edgesob.c | |||
Run the a.out file | |||
./a.out lena.bmp | |||
Execute the gprof command, provide it with the executable file name and pipe the output to a text file. | |||
gprof -b a.out >result.txt | |||
The output of gprof: | |||
Flat profile: | |||
Each sample counts as 0.01 seconds. | |||
% cumulative self self total | |||
time seconds seconds calls Ts/call Ts/call name | |||
100.31 0.03 0.03 main | |||
0.00 0.03 0.00 4 0.00 0.00 getImageInfo | |||
0.00 0.03 0.00 1 0.00 0.00 copyColorTable | |||
0.00 0.03 0.00 1 0.00 0.00 copyImageInfo | |||
Call graph | |||
granularity: each sample hit covers 2 byte(s) for 33.23% of 0.03 seconds | |||
index % time self children called name | |||
<spontaneous> | |||
[1] 100.0 0.03 0.00 main [1] | |||
0.00 0.00 4/4 getImageInfo [2] | |||
0.00 0.00 1/1 copyImageInfo [4] | |||
0.00 0.00 1/1 copyColorTable [3] | |||
----------------------------------------------- | |||
0.00 0.00 4/4 main [1] | |||
[2] 0.0 0.00 0.00 4 getImageInfo [2] | |||
----------------------------------------------- | |||
0.00 0.00 1/1 main [1] | |||
[3] 0.0 0.00 0.00 1 copyColorTable [3] | |||
----------------------------------------------- | |||
0.00 0.00 1/1 main [1] | |||
[4] 0.0 0.00 0.00 1 copyImageInfo [4] | |||
----------------------------------------------- | |||
Index by function name | |||
[3] copyColorTable [2] getImageInfo | |||
[4] copyImageInfo [1] main |
Revision as of 20:43, 22 February 2012
Team Members
- Kevin Townsend
- Bhavani Satyanarayana Rao
- Chidvila Gaddam
Assignment1
Running the sample application with script files
- The runcp script located in the SampleAppVadd can be used to run the application in HW which sets the appropriate environment variables and runs the UserApp.exe export CNY_PDK_PROJ = ~/pdk_sample/cae_pers_vadd ./runcp
- The run script located in the SampleAppVadd can be used to run the application in SW
- The scripts above can be used to run the application on Simulator using the "-vsim" option which sets the environment variable CNY_CAE_EMULATOR to ./run_simulation ./runcp -vsim or ./run -vsim
Environment Variables | Software | ModelSim | Hardware |
---|---|---|---|
CNY_SIM_THREAD | libcpSimLib2.so | libcpSimLib2.so | unset |
CNY_CAE_EMULATOR | <location for CaeSimPers> | ./run_simulation | unset |
Changes made to run the application on ModelSim
- Setup as explained in here [[1]]
- Set the CNY_PDK_PROJ environment variable to the location of cae_pers_vadd export CNY_PDK_PROJ = ~/pdk_sample/cae_pers_vadd
- Copied Jones' my_makefile from the temp dir and replaced the makefile in CY_PDK_PROJ/testbench
- Add line to the makefile in testbench dir CNY_PDK_MODELSIM_USER_SIM_OPTIONS= -i -do "run -all"
- Modify the values of LIB_DIR and LDFLAGS from 32-bit to 64-bit as given below LIB_DIR = lib64 LDFLAGS = -m64
Error creating thumbnail: File missing
Extra Credit: Exploring gdb
- We invoked gdb using the gdb <programname> command or by using the run/runcp script files in with "-gdb" option gdb UserApp.exe or ./run -gdb Error creating thumbnail: File missing
- One can find different command classes on gdb by typing help.To get details on a particular command class/command, type help on gdb followed by the name of the command class/command Error creating thumbnail: File missing
- We explored some commands like run, start (to begin execution), stepi (for single instruction stepping into a file), kill (kill a running program) and quit on gdb Error creating thumbnail: File missing
Assignment2
About Sobel Algorithm
Sobel Algorithm is used for edge detection in image processing.The link[2] explains
- Why edge detection is important?
- How sobel algorithm uses the gradient method (jump in the pixel values along edges in the images compared to the pixels around it) to detect edges in images?
The Algorithm
- Use Sobel masks to find the gradient of a pixel w.r.t its 8 immediate neighboring pixel values. The Sobel masks are GX={(-1,0,+1),(-2,0,+2),(-1,0,+1)) which gives the gradient in the x direction and Gy={(+1,+2,+1),(0,0,0),(-1,-2,-1)} which gives the gradient in the x direction.
- Find the approximate magnitude of the gradient using the formula |G|=|Gx|+|Gy|
- Compare |G| against the threshold values (0 and 255 in our case). If (|G| > 255) then the pixel value is 0 in the output image. If (|G| < 0) then the pixel value is 255 in the output image.
- Repeat the above steps for all the pixels in the image
C code for Sobel Algorithm
Source: Edge Detection Tutorial-Author: Bill Green (2002)[3]
for(Y=0; Y<=(originalImage.rows-1); Y++) { for(X=0; X<=(originalImage.cols-1); X++) { sumX = 0; sumY = 0; /* image boundaries */ if(Y==0 || Y==originalImage.rows-1) SUM = 0; else if(X==0 || X==originalImage.cols-1) SUM = 0; /* Convolution starts here */ else { /*-------X GRADIENT APPROXIMATION------*/ for(I=-1; I<=1; I++) { for(J=-1; J<=1; J++) { sumX = sumX + (int)( (*(originalImage.data + X + I + (Y + J)*originalImage.cols)) * GX[I+1][J+1]); } } if(sumX>255) sumX=255; if(sumX<0) sumX=0; /*-------Y GRADIENT APPROXIMATION-------*/ for(I=-1; I<=1; I++) { for(J=-1; J<=1; J++) { sumY = sumY + (int)( (*(originalImage.data + X + I + (Y + J)*originalImage.cols)) * GY[I+1][J+1]); } } if(sumY>255) sumY=255; if(sumY<0) sumY=0; SUM = abs(sumX) + abs(sumY); /*---GRADIENT MAGNITUDE APPROXIMATION (Myler p.218)----*/ } *(edgeImage.data + X + Y*originalImage.cols) = 255 - (unsigned char)(SUM); /* make edges black and background white */ fwrite( (edgeImage.data + X + Y*originalImage.cols), sizeof(char), 1, bmpOutput);
Profiling C code Using gprof
Compile the c code with -pg option
gcc -pg -lm edgesob.c
Run the a.out file
./a.out lena.bmp
Execute the gprof command, provide it with the executable file name and pipe the output to a text file.
gprof -b a.out >result.txt
The output of gprof:
Flat profile: Each sample counts as 0.01 seconds. % cumulative self self total time seconds seconds calls Ts/call Ts/call name 100.31 0.03 0.03 main 0.00 0.03 0.00 4 0.00 0.00 getImageInfo 0.00 0.03 0.00 1 0.00 0.00 copyColorTable 0.00 0.03 0.00 1 0.00 0.00 copyImageInfo Call graph granularity: each sample hit covers 2 byte(s) for 33.23% of 0.03 seconds index % time self children called name <spontaneous> [1] 100.0 0.03 0.00 main [1] 0.00 0.00 4/4 getImageInfo [2] 0.00 0.00 1/1 copyImageInfo [4] 0.00 0.00 1/1 copyColorTable [3] ----------------------------------------------- 0.00 0.00 4/4 main [1] [2] 0.0 0.00 0.00 4 getImageInfo [2] ----------------------------------------------- 0.00 0.00 1/1 main [1] [3] 0.0 0.00 0.00 1 copyColorTable [3] ----------------------------------------------- 0.00 0.00 1/1 main [1] [4] 0.0 0.00 0.00 1 copyImageInfo [4] ----------------------------------------------- Index by function name [3] copyColorTable [2] getImageInfo [4] copyImageInfo [1] main