US 5,673,204 A · Loopback video preview for a computer display

Abstract

A video adapter and computer/video system generate a video output signal having a first format useable by other video equipment. This signal is then looped back through the video adapter to generate a signal in a second format suitable for previewing on a monitor or display. The video adapter includes at least first and second data rate changers (preferably FIFOs), a controller unit, and circuitry for scaling and color-space converting the computer-processed video into the second format. Externally provided video input is multiplexed to a rate-increasing FIFO whose output is coupled to an IOSIMM unit in the computer/video system for video processing, through a master rate-decreasing FIFO whose output is output-controlled, format-processed and provided as the first format output signal. The output-controlled signal is coupled to a scaler, color-space converter and passed to a master rate-increasing FIFO. The output from this FIFO is coupled to the loopback path, to the video adapter for processing into the second format for previewing. Various forms of externally-provided video, as well as internally generated or stored video may be processed for output and preview.

Claims20

Dependent claims

A system for internally providing video data for output in a first format and for processing said data for output in a previewable second format, the system useable with a computer processing sub-system that includes a central processor unit (CPU) and a memory coupled to said CPU to store said video data and a video buffer unit coupled to receive said video data from said memory and to output a signal in said previewable second format, the system comprising:

a video adapter, coupled to said CPU, including:
a controller unit;
a master data rate-decreasing unit having an output coupled to an input of said controller unit;
a video scaling-color-space converting unit having an input coupled to an output of said controller unit;
a master data rate-increasing unit having an input coupled to an output of said video scaling-color-space converting unit and having an output that is fed back to an input of said master data rate-decreasing unit;
said CPU causing said video data to be coupled to said video adapter, said master data rate-decreasing unit, and said controller unit such that said controller unit outputs a video signal in said first format;
said controller unit further providing a signal to said video scaling-color-space converting unit, whose output is increased in data rate by said master data rate-increasing unit and coupled as an input to said computer processing sub-system for storage and coupling to said video buffer unit, said video buffer unit outputting a signal in said previewable second format.

4 more elements

A system for receiving at least one externally-provided video signal to be output in a first format and to be output in a previewable second format, the system useable with a computer processing sub-system that includes a central processor unit (CPU) and a memory coupled to said CPU to store said video data and a video buffer unit coupled to receive said video data from said memory and to output a signal in said previewable second format, the system comprising:

a video adapter, coupled to said CPU, including:
a controller unit;
a master data rate-decreasing unit having an output coupled to an input of said controller unit;
a video scaling-color-space converting unit having an input coupled to an output of said controller unit;
and
a master data rate-increasing unit having an input coupled to an output of said video scaling-color-space converting unit and having an output that is fed back to an input of said master data rate-decreasing unit.

3 more elements

In a video system comprising a computer processing sub-system that includes central processing unit (CPU), memory coupled to said CPU, a video buffer unit coupleable to said memory and outputting a signal in a previewable second format, said video system further comprising a video adapter, coupled to said CPU;

a method for processing video, whether externally input to said video adapter, stored in said memory, or generated by said computer processing sub-system, and for outputting said video in a first format and for outputting said previewable second format, the method including the following steps:
(a) processing said video in said computer processing sub-system and storing processed said video in said memory;
(b) feeding-back processed said video from said memory to said video adapter, and within said video adapter reducing a data rate of the fed-back video and format-processing the reduced data rate video for output as said first format signal;
(c) within said video adapter, size scaling and color-space converting, as necessary, the reduced data rate video and increasing a data rate of the resultant video signal;
(d) coupling said resultant video signal to an input of said video adapter for storage therein;
and
(e) outputting from storage in said video adapter said resultant video as said previewable second format video.

4 more elements

Dependencies are inferred from the claim text.

Loopback video preview for a computer display

Life of this patent

Loopback video preview for a computer display

Life of this patent

Abstract

Claims20