[Ffmpeg-cvslog] r5577 - trunk/libavcodec/flacenc.c

[Justin Ruggles]

Justin Ruggles wrote:
> Michael Niedermayer wrote:
> 
>>Hi
>>
>>On Sun, Jul 02, 2006 at 06:57:30PM +0100, M?ns Rullg?rd wrote:
>>
>>
>>>michael <subversion at mplayerhq.hu> writes:
>>>
>>>
>>>
>>>>Author: michael
>>>>Date: Sun Jul  2 15:14:04 2006
>>>>New Revision: 5577
>>>>
>>>>Modified:
>>>>  trunk/libavcodec/flacenc.c
>>>>
>>>>Log:
>>>>3 lines while -> 1 line for loop 
>>>>
>>>>Modified: trunk/libavcodec/flacenc.c
>>>>==============================================================================
>>>>--- trunk/libavcodec/flacenc.c	(original)
>>>>+++ trunk/libavcodec/flacenc.c	Sun Jul  2 15:14:04 2006
>>>>@@ -788,13 +788,11 @@
>>>>{
>>>>    int porder, max_parts;
>>>>
>>>>-    porder = max_porder;
>>>>-    while(porder > 0) {
>>>>+    for(porder = max_porder; porder > 0; porder--) {
>>>>        max_parts = (1 << porder);
>>>>        if(!(n % max_parts) && (n > max_parts*order)) {
>>>
>>>Wouldn't (n & (max_parts - 1)) do the same thing a tad faster?  n is
>>>always positive so there should be no surprises.
>>
>>
>>yes, and furthermore iam pretty sure the whole can be done without a loop
>>something based on av_log2(n ^ (n-1)) or similar
>>and iam unsure if n > max_parts*order is correct which was the reason why
>>i didnt change anything in that line, i wanted to check that first ...
>>
>>
>>[...]
> 
> 
> i finally figured it out. this patch works. it also fixes a couple bugs
> related to partition order.
> 
> thanks!
> -justin
> 

ok, so i went to bed and then this idea popped into my head, so I got
back up and made a better patch. :)

-justin

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