什么是 AV_SAMPLE_FMT_FLT

Question

SwrContext *swr_ctx = swr_alloc_set_opts(NULL,                          
                        AV_CH_LAYOUT_STEREO,
                        AV_SAMPLE_FMT_FLT,
                        sample_rate,
                        pCodecParameters->channel_layout,                                                                               
                  
                        pCodecParameters->format,
                        pCodecParameters->sample_rate,                          
                        0,
                        NULL);

what exactly AV_SAMPLE_FMT_FLT is? i already read docs but i want to know that what is float layout means in the context of Audio. How actually binary data of audio will look in that format.

Answer 1

It means every sample is in single buffer and per sample data is 32bit float. Buffer AFAIK structured like this:

[SAMPLE_CH0][SAMPLE_CH1]...[SAMPLE_CHn]
[SAMPLE_CH0][SAMPLE_CH1]...[SAMPLE_CHn]

So on so forth. This repeats the number of "samples" times.
I may be wrong though, you need to check it yourself.