artem said:Really it will be too hard to make a usb host in atmega and find and implement webcam control protocol Protocol mostlyis not pulished by manufactorer , so you have to dig linux driver or references to them for specific webcam or better for specific camera controller chip inside webcam. Theoretically it is possible but practically is not feasible . There are a lot of projects for direct camera sensor connection to avr using parallel interface - that sounds better and you can leave pic psotprocessing to PC and send data by uart or usb (see application note from atmel). Note that camera resolution is limited by avr processing capability. To have higher resolution - you can use cpld or glue logic based frame grabber which stores one or more frame in ram at clock high rate, then slow fetch by avr fromsram later.
Search this forum - there should be links to projects .
louisnells said:When a camera provide a USB interface it will be through one of the well defined USB device classes. All these class specifications are freely available from **broken link removed**. And most of the cameras provide a USB Mass Storage Class interface. ie: the camera will be acting like a storage device with FAT32 (or some other FS) filesystem on it. So all we have to do is to implement a USB Mass Storage Class device interface and some way to browse through the FS (FAT32) in firmware.
But if its a video camera then the interface can be MSC or Video Device Class.
Also its possible to implement the still camera using Still Imaging Class.
But all these classe drivers are already implemented as standard interfaces in most of the OSs like Windows & LINUX. So thats why when ever you plugin your flash drive or USB HDD on to computer we are able to access it as a usual disk drive. None of these drivers has to be coded again.
artem said:Really it will be too hard to make a usb host in atmega and find and implement webcam control protocol Protocol mostlyis not pulished by manufactorer , so you have to dig linux driver or references to them for specific webcam or better for specific camera controller chip inside webcam. Theoretically it is possible but practically is not feasible . There are a lot of projects for direct camera sensor connection to avr using parallel interface - that sounds better and you can leave pic psotprocessing to PC and send data by uart or usb (see application note from atmel). Note that camera resolution is limited by avr processing capability. To have higher resolution - you can use cpld or glue logic based frame grabber which stores one or more frame in ram at clock high rate, then slow fetch by avr from sram later.
Search this forum - there should be links to projects .
I was talking about frame grabbing from webcam. Are you about stil picture cams ?
louisnells said:But the frame format should have a standard encoding.
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