[FFmpeg-devel] [PATCH] Fix amrnb decoder scaling

[Ronald S. Bultje]

Hi,

On May 2, 2010, at 4:33 PM, Benjamin Larsson <banan at ludd.ltu.se> wrote:
> On 02/05/10 22:31, Martin Storsj? wrote:
>>
>> The output from the amrnb decoder is currently broken, since rev  
>> 22937. In
>> that commit, this chunk removed both scaling and clipping, even if  
>> only
>> clipping was intended to be removed:
>>
>> @@ -1048,10 +1046,6 @@ static int amrnb_decode_frame(AVCodecContext  
>> *avctx, void *data, int *data_size
>>                                               highpass_poles,  
>> highpass_gain,
>>                                               p->high_pass_mem,  
>> AMR_BLOCK_SIZE);
>>
>> -    for (i = 0; i<  AMR_BLOCK_SIZE; i++)
>> -        buf_out[i] = av_clipf(buf_out[i] * AMR_SAMPLE_SCALE,
>> -                              -1.0, 32767.0 / 32768.0);
>
> I'm quite sure the scaling can be added to some other step, so the  
> loop wouldn't be needed.

Yes, multiply it with highpass_gain in the function call before.

Ronald