[FFmpeg-devel] [PATCH] adpcm big frames decoding fix

[Baptiste Coudurier]

Hi

Michael Niedermayer wrote:
> Hi
> 
> On Sun, Aug 05, 2007 at 03:49:02AM +0200, Baptiste Coudurier wrote:
>> Hi
>>
>> Here is a patch to fix big adpcm swf frames decoding. Frames wrap at
>> 4096 samples per channel.
>>
>> Fix RamboMJPEGAVP6_1Mbps.swf.
> [...]
> 
>> Index: libavcodec/adpcm.c
>> ===================================================================
>> --- libavcodec/adpcm.c	(revision 9871)
>> +++ libavcodec/adpcm.c	(working copy)
>> @@ -1274,7 +1274,7 @@
>>      {
>>          GetBitContext gb;
>>          const int *table;
>> -        int k0, signmask, nb_bits;
>> +        int k0, signmask, nb_bits, count;
>>          int size = buf_size*8;
>>  
>>          init_get_bits(&gb, buf, size);
>> @@ -1286,12 +1286,13 @@
>>          k0 = 1 << (nb_bits-2);
>>          signmask = 1 << (nb_bits-1);
>>  
>> +        while (get_bits_count(&gb) <= size - 22*avctx->channels) {
> 
> are you sure this is not supposed to be above 
> nb_bits = get_bits(&gb, 2)+2;

I double checked, and the file doesn't decode in that case.

> it seems like bad design ...

:)
It seems quite correct according to what is written in specs at least.

-- 
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