Image display apparatus

An image display apparatus comprising:

• a display;
• a network interface configured to communicate with an external device;
• and
• a controller,
• wherein the controller is configured to:
• obtain device information from the external device;
• determine, based on the obtained device information, whether an audio signal processing specification of the external device satisfies a predetermined criterion;
• based on a determination that the specification of the external device satisfies the predetermined criterion, transmit first audio data for predetermined content being displayed through the display;
• based on a determination that the specification of the external device does not satisfy the predetermined criterion,
• process an audio signal corresponding to the first audio data according to the specification of the external device;
• generate second audio data corresponding to the processed audio signal;
• and
• transmit the second audio data to the external device,
• wherein the device information includes power information for audio output of the external device, and
• wherein the controller is configured to:
• determine, based on preset volume information of the image display apparatus, and the power information of the external device, an output gain of the external device;
• and
• transmit data for the determined output gain to the external device.