[FFmpeg-devel] [patch] support decoding png 1,2,4 bits

[Måns Rullgård]

Reimar D?ffinger wrote:
> Hello,
> On Thu, Feb 14, 2008 at 10:41:50AM +0100, Julien Reichel wrote:
>> +    if (src_bits==1){
>> +        for(j = 0;j < width; j+=8) {
>
> This will probably break badly if width is not divisible by 8?
>
>> +            v = src[0];
>> +            dst[0] = (v&0x80)>>7;
>> +            dst[1] = (v&0x40)>>6;
>> +            dst[2] = (v&0x20)>>5;
>> +            dst[3] = (v&0x10)>>4;
>> +            dst[4] = (v&0x08)>>3;
>> +            dst[5] = (v&0x04)>>2;
>> +            dst[6] = (v&0x02)>>1;
>> +            dst[7] = (v&0x01);
>
> (v >> 7) & 1;
> (v >> 6) & 1;
> (v >> 5) & 1;

Useless brackets.

> IMO would be much more readable.

Agree, especially without the brackets.

> In addition if speed does not matter (much), just using the bitstream
> reader would be much simpler as well (maybe 4 lines of code to handle
> _all_ cases), though it would require src to be padded, not idea if that
> is the case currently.

My thoughts as well.

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