#Input delay test plus#

That is, they have a fixed grid of pixels on the screen that show the image sharpest when running at the native resolution (so nothing has to be scaled full-size which blurs the image).

LCD, plasma, and DLP displays, unlike CRTs, have a native resolution. Investigations have been performed by several technology-related websites, some of which are listed at the bottom of this article. Possible culprits are the processing overhead of HDCP, Digital Rights Management (DRM), and also DSP techniques employed to reduce the effects of ghosting – and the cause may vary depending on the model of display. While the pixel response time of the display is usually listed in the monitor's specifications, no manufacturers advertise the display lag of their displays, likely because the trend has been to increase display lag as manufacturers find more ways to process input at the display level before it is shown.

#Input delay test plus#

This is done by storing several interlaced frames and then applying algorithms to determine areas of motion and stillness, and to either merge interlaced frames for smoothing or extrapolate where pixels are in motion, the resulting calculated frame buffer is then written to the display device.ĭe-interlacing imposes a delay that can be no shorter than the number of frames being stored for reference, plus an additional variable period for calculating the resulting extrapolated frame buffer delays of 16-32ms are common. In its simplest form, this processing may take several microseconds to occur.įor interlaced video, additional processing is frequently applied to deinterlace the image and make it seem to be clearer or more detailed than it actually is. For either over-the-air or cable TV, the same analog demodulation techniques are used, but after that, then the signal is converted to digital data, which must be decompressed using the MPEG codec, and rendered into an image bitmap stored in a frame buffer.įor progressive scan display modes, the signal processing stops here, and the frame buffer is immediately written to the display device. Image adjustments typically involve reshaping the signal waveform but without storage, so the image is written to the screen as fast as it is received, with only nanoseconds of delay for the signal to traverse the wiring inside the device from input to the screen.įor modern digital signals, significant computer processing power and memory storage is needed to prepare an input signal for display. The picture signal is minimally processed internally, simply for demodulation from a radio-frequency (RF) carrier wave (for televisions), and then splitting into separate signals for the red, green, and blue electron guns, and for the timing of the vertical and horizontal sync. For older analog cathode ray tube (CRT) technology, display lag is nearly zero, due to the nature of the technology, which does not have the ability to store image data before display.