Picture Processing; Audio Processing (During Record And Playback) - Canon PowerShot A30 Service Manual

CHAPTER 2. TECHNICAL DESCRIPTION

2.2.2 Picture Processing

1) The drive pulse of the CCD sensor is created by both clock from DSP and TG that is operated by
sync. signal.
The picture signal by the drive pulse is output from CCD sensor.
The output signal of the CCD picture is converted to the signal processing and the digital data by
the CDS and A/D converter, and is sent to the DSP.
2) The DSP circuit performs the following signal processing.
• Processes the picture data (using the SDRAM).
• Writes and reads the picture data to and from the CF card.
• Inputs the picture data to the CPU.
• Outputs analog video signal to the LCD and VIDEO OUT.
3) The video signal that is supplied form the DSP is controlled by the LCD driver and is displayed
on the LCD. The video amplifier is activated when the video jack is inserted to the video jack or
AV jack and drives the video signal in 75 Ω.

2.2.3 Audio Processing (During record and playback)

1) During animation recording.
• The microphone audio signal is converted to the digital data by CPU and is recorded.
2) During playback, the data is converted back to the analog audio signal and is output to the AV
jack.
Note: Installed in the A40 model only. (Audio cannot be played back by camera.)
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