Texas Instruments SPRAA56 appendix Expected Values Delivered to the Message Log, Debug Mode

SPRAA56

5.3.2 Expected Values Delivered to the Message Log

CPU load, latency, time to process 30 frames, and bitrate are all sent to the Message Log rather than the Statistics View window. Table 2 shows the expected and measured values.

Table 2.	Expected and Measured Logged Benchmarks
Benchmark		Expected Value	Measured Value	Your Measurement
latency		<33 ms	26 ms
CPU load		80-90%	84-86%
bitrate		4084 kbps	4009-4117 kbps
Time to process 30 frames		1 second	1001-1004 ms

5.4Controlling the Run-Time Parameters Dynamically

After running the application on the EVM and gathering benchmarks, you may want to measure benchmarks and test operation with different frame rates, bitrates, or configurations. You can control such parameters at run-time through the GEL→h263rateControl menu commands. Some of the commands are:

•setFrameRate. Use this slider to set the frame rate to a value from 0 to 30.

•setBitRate. Type a target bitrate for the encoder algorithm between 32 and 15000.

•passthroughReference. Set to 1 to bypasses the decoder and output the frame captured by the encoder without any modification. Set to 0 to use the decoder.

•color. Set to 1 to enable color processing. Set to 0 to disable color processing. This slider can be used to benchmark the application with and without color processing enabled.

5.4.1 Debug Mode

The amount of data displayed in the Message Log in the default configuration may be more than what is required. By default, all benchmarks are reported every 30 frames. To control the displayed data, choose GEL→rtaMode and set the slider to one of the following 4 mode values:

1.ERRORS ONLY. This mode reports only dropped frames or other errors.

2.CPU LOAD ONLY. This mode displays only the CPU load and frame type every N frames.

3.EVERY N FRAMES. This mode displays more complete benchmarking every N frames, including bitrate and frame skip reports.

4.EVERY I FRAME. This mode displays more complete benchmarking when an I (intracoded) frame is encoded. The distance between I frames is an algorithm parameter that is set to 132 by default, but can be changed at runtime to another value if necessary.

DSP/BIOS Real-Time Analysis (RTA) and Debugging Applied to a Video Application 25