Method of transmitting data

A multi-channel Digital Video Recorder (DVR) for transmitting image data, the device comprising:

• a data processor configured to:
• receive, from a plurality of cameras via a plurality of channels, a plurality of image data, respectively,
• downsample each of the plurality of image data into N layers corresponding to different display sizes for each of the plurality of image data, respectively, each of the N layers being smaller in size than an original size of each of the corresponding plurality of image data, an nth layer of the N layers being generated by collecting every nth pixel of each of N pixels of each of the corresponding plurality of image data in a lateral and vertical direction, where n is a natural number smaller than or equal to N and N is a natural number larger than 1, and
• compress the downsampled N layers for the different display sizes of each of the corresponding plurality of image data;
• and
• a transmitting unit to transmit, to a counterpart DVR connected to the multi-channel DVR via a network, at least one of the downsampled and compressed N layers for a particular size for displaying each of more than one of the corresponding plurality of image data on the counterpart DVR,
• wherein, the transmitting unit is configured to transmit a first layer of each the more than one of the downsampled and compressed N layers for displaying each of more than one of the corresponding plurality of image data of the particular size to the counterpart DVR and subsequently transmit remaining layers of each the more than one of the downsampled and compressed N layers for displaying each of more than one of the corresponding plurality of image data of the particular size to the counterpart DVR, and
• wherein, when a display size of the counterpart DVR for a particular image data of the corresponding plurality of image data is greater than a screen size of the downsampled and compressed N layers for displaying the particular image data of the particular size, all of the downsampled and compressed N layers for displaying the particular image data of the particular size are transmitted by the transmitting unit.