search for: qlp

Hi all, I was investigating the behaviour of the -p switch of flac. This switch should enable exhaustive search for the optimal qlp coefficient precision, but the resulting files are usually 0.5% larger then when not using the switch. I stumbled upon this code in stream_encoder > if(encoder->protected_->do_qlp_coeff_prec_search) { > min_qlp_coeff_precision = FLAC__MIN_QLP_COEFF_PRECISION; > /* try to...

stream_encoder.c has the following code: /* try to keep qlp coeff precision such that only 32-bit math is required for decode of <=16bps streams */ if(subframe_bps <= 16) { ... But FLAC can convert 16-bit input to 17-bit if mid-side coding is used. So, does it make sense to compare subframe_bps with 17? (The patch is attached. What do you think ab...

Martijn van Beurden wrote: > Yes, but that MAX value is used to loop over the > qlp_coeff_precision values between MIN and MAX. So, if the > qlp_coeff_precision value is limited in the loop but MAX is not > limited, the loop does the exact same thing multiple times: a > waste of time. Therefore, only the MAX should be limited. > > I don't think the logic is need...

...t/archzoom.cgi/eric@petta-tech.com--2005a-normalperson/flac--ipod--1.1.0--patch-19/src/libFLAC/arm/lpc_asm.s -- Eric Wong --- orig/src/libFLAC/lpc.c +++ mod/src/libFLAC/lpc.c @@ -293,6 +293,209 @@ void FLAC__lpc_restore_signal(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]) { + register const FLAC__int32 *qlp0 = &qlp_coeff[(order-1)]; + register FLAC__int32 sum; + register const FLAC__int32 *history, *qlp; + + history = &data[(-order)]; + + switch (order) { + case 12: + for( ; data_len != 0; -...

..., so look at the change log to see why the change came about. Brian Willoughby Sound Consulting On Apr 18, 2015, at 12:20 PM, Brian Willoughby <brianw at audiobanshee.com> wrote: > Hmm, I don't know the history of the code, but flac 1.2.1 stream_encoder.c has > > min_qlp_coeff_precision = FLAC__MIN_QLP_COEFF_PRECISION; > /* try to ensure a 32-bit datapath throughout for 16bps(+1bps for side channel) or less */ > if(subframe_bps <= 17) { > max_qlp_coeff_precision = min(32 - subframe_bps - lpc_order, FLAC__MAX_QLP_COEFF_PRECISI...

...@@ <span class="argument">--no-mid-side</span><br /> <span class="argument">--no-ogg</span><br /> <span class="argument">--no-padding</span><br /> - <span class="argument">--no-qlp-coeff-precision-search</span><br /> + <span class="argument">--no-qlp-coeff-prec-search</span><br /> <span class="argument">--no-residual-gnuplot</span><br /> <span class="argument">--no-residual-tex...

...;=8) (not a problem for me right now), but the inner loop for larger orders could be done using Duff's device and still be fast without getting much bigger. I reading up on ARM assembly right now. void FLAC__lpc_restore_signal(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]) { unsigned i; FLAC__int32 sum; const FLAC__int32 *history, *qlp; const int tmp = (0 - order - 1); for(i = data_len; i != 0; --i) { sum = 0; qlp = &qlp_coeff[order]; history = &data[tmp]; switch (order) { cas...

Brian Willoughby wrote: > Ok, I just did a comparison of 1.2.1 with 1.3.2, and the change you're > suggesting was already there before. So, now the question becomes: why > was the code changed in the first place? There should be some indication of why in the git history. Erik -- ---------------------------------------------------------------------- Erik de Castro Lopo

Martijn van Beurden wrote: > Yes, indeed. I removed the 17-bits part because I just matched > the code in evaluate_lpc_subframe_ with the process_subframe_ > code. It appears it only makes sense that those two pieces code > are the same. A bit of history: 1) The conditional "if(subframe_bps <= 16)" was added to evaluate_lpc_subframe_() in the commit

Erik de Castro Lopo wrote: > There should be some indication of why in the git history. http://git.xiph.org/?p=flac.git;a=commitdiff;h=27846708fe6271e5e3965a4bbad99baa1ca24c49 Now I remember a discussion about a bug in -p switch: the old code substracts lpc_order instead of FLAC__bitmath_ilog2(lpc_order), and this commit fixes this. It seems that the logic in process_subframe_() and in

Martijn van Beurden wrote: > Or maybe the question is: why is this code in evaluate_lpc_subframe anyway, > i.e, why is this code duplicated? If process_subframe_ sets the > qlp_precision for evaluate_lpc_subframe, why should the latter ignore that? > > We can only speculate about this, but I think this code has been duplicated > by accident, and therefore it wasn't changed as the code shouldn't have > been there in the first place. Well, the code in p...

Pulled from my Arch archive, this following patch seems to have made quite a difference in getting my ARM7TDMI chip to play FLAC (compression levels 0-2) on my ipod. I don't have benchmarks with hard numbers, but playing with skips vs playing without skips is a fairly noticeable difference. memcpy and memset on uClibc are optimized in asm for the ARM7TDMI in uClibc. Other hardware/libc

...roblem : i've downloaded centos 3.4 on i386 the md5sum of CD1's iso file is OK i burn it on a CD with NERO and i have this problem in CD1 of centos 3.4 for i386 : ---------------------------- # file perl-5.8.0-88.9.i386.rpm perl-5.8.0-88.9.i386.rpm: RPM v3 bin i386 perl-5.8.0-88.9 # rpm -qlp perl-5.8.0-88.9.i386.rpm erreur: perl-5.8.0-88.9.i386.rpm: signature V3 DSA: BAD, key ID 025e513b # rpm -qpi perl-5.8.0-88.9.i386.rpm erreur: perl-5.8.0-88.9.i386.rpm: signature V3 DSA: BAD, key ID 025e513b ------------------------- SO : do you see the same thing ??? is it a problem of Nero or C...

Laurent Moix wrote: > Hi, > > I try to install shorewall 2.2 on suse 9.2. > > # rpm -ivh --nodeps /root/shorewall-2.2.1-1.noarch.rpm > Preparing... ########################################### [100%] > 1:shorewall ########################################### [100%] > shorewall: unknown service > shorewall: not a runlevel service > >

Hi everybody, We have FLAC supported for input/output in REAPER (http://www.reaper.fm), and the problem is that when writing 24 bit FLAC files, the data isn't compressed (i.e. the FLAC is slightly larger than if it was writing to .WAV). The files play back fine, however, and 16 bit mode works great. We're using flac-1.1.2, built on win32 with MSVC6 w/ SP5 + VCPP, and NASM version 0.98.39

....TP +\fB--no-preserve-modtime\fR +.TP +\fB--no-keep-foreign-metadata\fR +.TP \fB--no-exhaustive-model-search\fR .TP +\fB--no-force\fR +.TP \fB--no-lax\fR .TP \fB--no-mid-side\fR @@ -307,6 +322,8 @@ Force input (when encoding) or output (when decoding) to be treated as raw sampl .TP \fB--no-qlp-coeff-precision-search\fR .TP +\fB--no-replay-gain\fR +.TP \fB--no-residual-gnuplot\fR .TP \fB--no-residual-text\fR diff --git a/man/flac.sgml b/man/flac.sgml index 3b96644..587e377 100644 --- a/man/flac.sgml +++ b/man/flac.sgml @@ -698,11 +698,13 @@ <term><option>--no-preserve-...

On Thu, 27 Jan 2005, John Steele Scott wrote: > That looks fine to me as well. However, the best solution is something which > Luca suggested a few months ago, which is to use the functions defined in > altivec.h. These are C functions which map directly to Altivec machine > instructions. I am willing to help out, but I don't find the current lpc_asm.s > very easy to follow, and

...ual values set for each level are: * <table> * <tr> - * <td><b>level</b><td> - * <td>do mid-side stereo<td> - * <td>loose mid-side stereo<td> - * <td>apodization<td> - * <td>max lpc order<td> - * <td>qlp coeff precision<td> - * <td>qlp coeff prec search<td> - * <td>escape coding<td> - * <td>exhaustive model search<td> - * <td>min residual partition order<td> - * <td>max residual partition order<td> - * <td>rice parameter...

When using the -p switch during encoding, the encoder should try different qlp predictor precision steps. However, some faulty code was too severely restricting the possible steps. This patch lifts the restriction to match a restriction coded a little further in the process. This doesn't make using -p worth your while, but at least it doesn't create larger files now -...

Hello is there any fastcgi rpm available. I downloaded fastcgi rpm from pbone.net, but it does not contain mod_fastcgi.so what about srpm ? http://rpm.pbone.net/index.php3/stat/4/idpl/612033/com/mod_fastcgi-2.4.0-1.i386.rpm.html thanks for help