similar to: mdct.c optimization

In mdct.c there's some functions including some-point butterfly. In 32-point and 16-point there are calling of smaller-point function everytime twice on each half of data. When I looked on it I found that's just linear algebra. So it can be rewritten to matrix multiplication. Some one can say: there's optimization on in register working. But imagine there's one calling 32-point,

I did composition of butterfly8 and butterfly16 and I found, that these functions are well decomposed - decomposition doesn't lower computional speed. On the other hand the same can be done with butterfly8 - decomposition to butterfly4 (further decomposition is not possible) but there's no reason to do this. I think little improvement can be done by inlining them. Compiler and processor

Hello I have a table describing butterfly range traits. It is composed of three columns as below Species name range size (X) latitude of range midpoint (Y) There are 11 kinds of butterflies. Each has its range size, and the latitude of each range midpoint ranges from 9 to 19. I would like to have the average range size of every degree of latitude. For example, the average range

Hello I have a table describing butterfly range traits. It is composed of three columns as below Species name range size (X) latitude of range midpoint (Y) There are 11 kinds of butterflies. Each has its range size, and the latitude of each range midpoint ranges from 9 to 19. I would like to have the average range size of every degree of latitude. For example, the average range

Hello One of my packages, untb_1.3-2, passes R CMD check under MacOSX (and apparently the systems used in the package check summary page on CRAN) but fails with the following message on R-2.6.0.tgz compiled last night on my (home) linux box. I hasten to add that I have never seen this error before on home-compiled pre-releases of R-2.6.0. Can anyone help me understand what is going on?

Hello , I want to compare two quadratic regression models with non-parametric bootstrap. However, I do not know which R package can serve the purpose, such as boot, rms, or bootstrap, DeltaR. Please kindly advise and thank you. Elaine The two quadratic regression models are y1=a1x^2+b1x+c1 y1= observed migration distance of butterflies() y2=a2x^2+b2x+c2 y2= predicted migration distance of

Hello, I am work with a linear regression model: y=ax+b with the function of lm. y= observed migration distance of butterflies x= predicted migration distance of butterflies Usually the result will show if the linear term a is significantly different from zero based on the p-value. Now I would like to test if the linear term is significantly different from one. (because I want to know

Hello, I have two very rudimentary questions regarding the random effects terms in the lme and lmer functions. I apologize if this also partly strays into a general statistics question, but I'm a bit new to this all. So hopefully it'll be a quick problem to sort out... Here is my experimental setup: I raised butterflies in 5 different testing chambers all set to different

libvorbis does not currently have any simd/vectorization. Following patches add generic framework for simd/vectorization and on top, add ARM-NEON simd vectorization using intrinsics. I was able to get over 34% performance improvement on my Beaglebone Black which is single Cortex-A8 based CPU. You can find more information on metrics and procedure I used to measure at

Dear Experts, Can anybody please direct me to proper MDCT theory reference which will help me understand the code better? I'm trying to optimize MDCT for a embedded platform. So need good understanding about theory behind & implementation. Thanks in advance for your time. Warm Regards, Mahantesh -------------- next part -------------- An HTML attachment was scrubbed... URL:

Hi vorbis-dev! I'm working with Pattara in the oggonachip project, and wondering about the implementation of mdct.c as hardware. According your recomendations about using the floating point version, I would say, we have to implement the integerized version of mdct as a core, and use the fpu only to round the input values. By doing that, you think the result would be still acceptable? How

Hi, The other day on IRC myself, Chandler, Hal and Pablo discussed recursive inlining. I've pondered a bit since then, and thought I'd get some background on the list with the aim of stimulating discussion. Our goal is to inline recursive functions. We have several workloads with recursive calls, and inlining them to a certain degree can improve performance by up to 30%. Inlining

Hi, Can someone tell me which MDCT and invMDCT equation uses? I implemented the invMDCT one given in eusipco.corrected.ps file (handed out by Monty way back) and it produces different time domain samples. I tried both the FFT method and the slow way directly from the equation and couldn't reproduce the results from the original code. This leads me to believe that the forward MDCT used in

Dear all In the paper section describes how CELT and SILK had implemented a look/up head delay of (2.5ms), (5ms) respectively , could you explain me> 1) those values are fixed. 1) how you guarantee those values independent of the architecture's performance. Thanks so much On Tue, Apr 18, 2017 at 10:05 AM, Diego Alejandro Parra Guzman < daparrag at correo.udistrital.edu.co>

Hi, I have a doubt regarding MDCT window size for OggVorbis decoder. Can the MDCT window size vary from 64 samples to 8192 samples? Specification says that "legal frame sizes are powers of two from 64 to 8192 samples" . Is this same as MDCT window size? Please help me out.. Regards, shikha <p>--- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage:

Hi, as we are trying to implement MDCT in hardware, we are caring now about the "n" (size of input and output vectors to and from MDCT). As I have looked in the code, this "n" is chosen from the Ogg/Vorbis stream data in info.c:_vorbis_unpack_info() which means this "n" can vary aribitrarily (as the power of 2) depending only on the value got from song data? or is

Dear all I'm working on the implementation of the MDCT for the processor ARM-Cortex-M4 I'm trying to replicate the behavior of the MDCT for several overlapped values however I realized that current implementation of the MDCT is very close to the theory only in case in which we have and overlap exactly equal to N/2 where N is the size of the input vector as is shown in the examples for

http://en.wikipedia.org/wiki/Modified_discrete_cosine_transform is an OK place to start. On Mon, Jul 8, 2013 at 7:33 AM, Mahantesh Belakhindi <girishec28 at gmail.com>wrote: > Dear Experts, > > Can anybody please direct me to proper MDCT theory reference which will > help me understand the code better? > > I'm trying to optimize MDCT for a embedded platform. So need

Hi vorbis-dev, I'm investigating the mdct* function in libvorbis and writing a small client program to test it. I found that I have to set ARRAYSIZE when mdct_init(lookup, ARRAYSIZE) to minimum value of 62 otherwise it will segfault with mdct_backward. Is there any lower limit or it is more likely that my code has bug? Thank you very much, Pattara -- Please avoid sending me Word or

In vorbis/lib/mdct.h the following are defined: for integer: #define TRIGBITS 14 #define cPI3_8 6270 #define cPI2_8 11585 #define cPI1_8 15137 #define FLOAT_CONV(x) ((int)((x)*(1<<TRIGBITS)+.5)) for floats: #define cPI3_8 .38268343236508977175F #define cPI2_8 .70710678118654752441F #define cPI1_8 .92387953251128675613F #define FLOAT_CONV(x) = x Could someone explain where these values