[FFmpeg-devel] [PATCH] mpeg2: fix block_last_index when mismatch control modifies last coeff

[Måns Rullgård]

Michael Niedermayer <michaelni at gmx.at> writes:

>> +static inline void idct_dc_add(uint8_t *dst, int line_size, int dc)
>> +{
>> +    int x, y;
>> +    uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
>
>> +    dc = (16383 * dc + 1024) >> 11;
>> +    dc = (16383 * (dc + 32)) >> 20;
>
> dc= (dc + (i<0) + 3)>>3;

i?

> or
> dc= (dc*2047 + 8192)>>14;
>
>> +    for (y = 0; y < 8; y++, dst += line_size) {
>> +        for (x = 0; x < 8; x++) {
>> +            dst[x] = cm[dst[x] + dc];
>> +        }
>> +    }
>
> cm += dc;
> can be done outside the loop

I noticed today this could be done in quite a few places throughout
existing code.

>> Index: libavcodec/h264.h
>> ===================================================================
>> --- libavcodec/h264.h	(revision 23459)
>> +++ libavcodec/h264.h	(working copy)
>> @@ -735,22 +735,6 @@
>>   1+5*8, 2+5*8,
>>  };
>>  
>> -static av_always_inline uint32_t pack16to32(int a, int b){
>> -#if HAVE_BIGENDIAN
>> -   return (b&0xFFFF) + (a<<16);
>> -#else
>> -   return (a&0xFFFF) + (b<<16);
>> -#endif
>> -}
>> -
>> -static av_always_inline uint16_t pack8to16(int a, int b){
>> -#if HAVE_BIGENDIAN
>> -   return (b&0xFF) + (a<<8);
>> -#else
>> -   return (a&0xFF) + (b<<8);
>> -#endif
>> -}
>> -
>
> moving these or anything else to a common place is ok of course

I suggest alongside the 8x4 Ronald added today.

-- 
M?ns Rullg?rd
mans at mansr.com