DCT-II and DCT-III implementation problem

Status
Not open for further replies.

8macius7

Newbie level 2
Joined
Apr 16, 2011
Messages
2
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,295
Hello guys

I'm implementing DCT and IDCT algorithms in mathematica, and i have following problem. DCT-II transformation looks good (the results are the same like in the book), but i cant get back to original data.

Results are very poor:

DCT input Data:
Code:
DCT[{12, 10, 8, 10, 12, 10, 8, 11}]
DCT result:
Code:
{28.6378,0.571202,0.46194,1.757,3.18198,-1.72956,0.191342,-0.308709}
IDCT input Data:
Code:
IDCT[{28.6, 0.6, 0.5, 1.8, 3.2, -1.8, 0.2, -0.3}];
IDCT result:
Code:
{11.465,14.2118,12.149,14.1194,16.2048,14.1817,12.132,15.1873}
As you can see the results of DCT-III are very, very poor. I attached my algorithm written in mathematica, based on D. Salomon Data Compression The Complete Reference book.

Thanks for any help!:wink:
Edit:
added attachment
 

Attachments

  • DCT.nb.pdf
    107.6 KB · Views: 107
Last edited:

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…