[Sound-open-firmware] [PATCH] SRC: Support block sizes near or equal to period length

[Liam Girdwood]

On Thu, 2017-10-05 at 18:57 +0300, Seppo Ingalsuo wrote:
> This patch decouples the first and second stage in two phase conversion
> that is used for out/in rate fractions with high numerator or denominator
> value. For e.g. 44.1 -> 48 kHz 160/147 fraction the 1st 8/7 stage and
> 2nd 20/21 stage are executed number of times close to period length in
> time used for the scheduling rate. The number of consumed and produced
> samples per copy() is no more constant. The latency of 44.1 kHz is
> decreased about 2 ms and processing load is less variable.
> 
> This patch removes mute feature due to non-compatibility with variable
> length data processing. It can be introduced later if needed as different
> implementation.
> 
> The polyphase filter is also optimized slightly. More optimizations will
> follow.
> 
> Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo at linux.intel.com>
> ---
>  src/audio/src.c      | 354 +++++++++++++++++++++----------------------
>  src/audio/src_core.c | 412 ++++++++++++++++++++++++---------------------------
>  src/audio/src_core.h |  27 +++-
>  3 files changed, 395 insertions(+), 398 deletions(-)

Applied.

Thanks

Liam