summaryrefslogtreecommitdiffstats
path: root/doc/swresample.txt
diff options
context:
space:
mode:
Diffstat (limited to 'doc/swresample.txt')
-rw-r--r--doc/swresample.txt46
1 files changed, 46 insertions, 0 deletions
diff --git a/doc/swresample.txt b/doc/swresample.txt
new file mode 100644
index 0000000..4daa181
--- /dev/null
+++ b/doc/swresample.txt
@@ -0,0 +1,46 @@
+ The official guide to swresample for confused developers.
+ =========================================================
+
+Current (simplified) Architecture:
+---------------------------------
+ Input
+ v
+ __________________/|\___________
+ / | \
+ / input sample format convert v
+ / | ___________/
+ | |/
+ | v
+ | ___________/|\___________ _____________
+ | / | \ | |
+ | Rematrix | resample <---->| Buffers |
+ | \___________ | ___________/ |_____________|
+ v \|/
+Special Converter v
+ v ___________/|\___________ _____________
+ | / | \ | |
+ | Rematrix | resample <---->| Buffers |
+ | \___________ | ___________/ |_____________|
+ | \|/
+ | v
+ | |\___________
+ \ | \
+ \ output sample format convert v
+ \_________________ | ___________/
+ \|/
+ v
+ Output
+
+Planar/Packed convertion is done when needed during sample format convertion
+Every step can be skiped without memcpy when its not needed.
+Either Resampling and Rematrixing can be performed first depending on which
+way its faster.
+The Buffers are needed for resampling due to resamplng being a process that
+requires future and past data, it thus also introduces inevitably a delay when
+used.
+Internally 32bit float and 16bit int is supported currently, other formats can
+easily be added
+Externally all sample formats in packed and planar configuration are supported
+Its also trivial to add special converters for common cases
+If only sample format and or packed/planar convertion is needed it
+is performed from input to output directly in a single pass with no intermediates.
OpenPOWER on IntegriCloud