Team Slytherin

Team Members

• Kevin Townsend
• Bhavani Satyanarayana Rao
• Chidvila Gaddam

Assignment1

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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

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Assignment2

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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);