Changes between Version 15 and Version 16 of user_applications

Timestamp:

Nov 21, 2015, 2:43:05 PM (9 years ago)

Author:

alain

Comment:

--

user_applications

@@ -175 +175 @@
 == __mjpeg__ ==
 
-This multi-threaded application makes the decompression of a MJPEG bit-stream contained in a file.
+This multi-threaded application makes the decompression of a MJPEG bit-stream contained in a file, an display the stream of images on the Frame Buffer.
 It illustrates the "multi pipe-line" parallelism. It uses the message passing programming model, on top of the POSIX threads API, and the MWMR communication middleware.
 The application is described as a TCG (Task and Communication Graph), and all communications between threads uses MWMR channels.
 Each pipeline decompress one complete image, and there is one pipe-line per cluster.
-It uses the chained buffer DMA component to display the stream of decompressed images on the graphic display.
+It uses the chained buffer DMA component to display the stream of decompressed images.ç!!l:=m
 It contains 6 types of threads (plus the "main" thread, that makes initialisation), and 7 types of MWMR communication channels:
  * the TG thread dispatch the bit-stream to the pipeline. It is only mapped in cluster[0,0].
  * the 5 threads implementing the pipeline (DEMUX, VLD, IQZZ, IDCT, LIBU) are replicated in all clusters.
  * the 7 MWMR channels are replicated in all clusters.
+The image throughput is actually bounded by the TG task that cannot be parallelized.
 
 The hardware constraints are the following
@@ -191 +192 @@
  * It uses one TTY terminal shared by all tasks.
 
+All parameters (number of images, depths of communication channels, debug variables) are defined in the [source:soft/giet_vm/applications/mjpeg/mjpeg.h mjpeg.h] file.
+
 The source code can be found [source:soft/giet_vm/applications/mjpeg/mjpeg.c here], and the mapping is defined [source:soft/giet_vm/applications/mjpeg/mjpeg.py here].