Video display system and video display method

1. A video display system comprising:

an imaging device that sequentially generates captured video data of a first gradation having a first bit number by imaging and sequentially outputs display video data of a second gradation having a second bit number smaller than the first bit number, based on the captured video data; and

a display apparatus that sequentially displays a video based on the display video data from the imaging device,

wherein, in the display apparatus, when a plurality of frames continuous in time series are displayed based on the display video data, although a first gradation value based on the first gradation of a predetermined pixel included in the captured video data corresponding to the plurality of frames does not change in the imaging device, a second gradation value based on the second gradation of the predetermined pixel included in the display video data corresponding to the plurality of frames varies.

2. The video display system of claim 1 ,

wherein the imaging device includes a camera that generates the captured video data and a modulator that generates the display video data by quantizing the captured video data, and

wherein an amount of variation of the second gradation value in the display apparatus correlates with a gradation value component smaller than the second gradation generated by the quantization of the modulator.

3. The video display system of claim 1 , wherein the display apparatus includes

a display that displays a video,

a first video input interface that receives the display video data from the imaging device at a frame rate exceeding 60 fps,

a second video input interface that receives external video data from an external apparatus different from the imaging device at a frame rate of 60 fps or less, and

a switch that selectively inputs the display video data from the first video input interface and the external video data from the second video input interface to the display device.

4. The video display system of claim 2 , wherein the modulator includes

a quantizer that sequentially outputs quantized data obtained by quantizing input data based on the captured video data into the display video data,

a storage that sequentially stores the quantized data output from the quantizer,

a difference calculator that sequentially calculates differences between the captured video data of the first gradation for a current frame and the quantized data for a previous frame stored in the storage, and

an integrator that sequentially outputs integral data obtained by sequentially integrating the differences output from the difference calculator as the input data of the quantizer.

5. The video display system of claim 2 , wherein the modulator includes

a quantizer that sequentially outputs quantized data obtained by quantizing input data based on the captured video data into the display video data,

a storage that sequentially stores the quantized data output from the quantizer,

an integrator that sequentially outputs integral data obtained by sequentially integrating the quantized data stored in the storage, and

a difference calculator that sequentially calculates differences between the captured video data of the first gradation and the integral data and sequentially outputs the calculated differences as the input data of the quantizer.

6. The video display system of claim 2 , wherein the modulator includes

an oscillator that sequentially generates variation value data having the second bit number statistically or stochastically,

an adder that sequentially adds the variation value data to the captured video data of the first gradation, and

a quantizer that sequentially outputs quantized data obtained by quantizing data output from the adder into the display video data of the second gradation.

7. A video display method performed by a video display system including an imaging device that sequentially generates captured video data of a first gradation having a first bit number by imaging and sequentially outputs display video data of a second gradation having a second bit number smaller than the first bit number, based on the captured video data, and a display apparatus that sequentially displays a video based on the display video data from the imaging device, the method comprising:

varying a second gradation value based on the second gradation of a predetermined pixel included in the display video data corresponding to a plurality of frames, in the display apparatus, when the plurality of frames continuous in time series are displayed based on the display video data, although a first gradation value based on the first gradation of the predetermined pixel included in the captured video data corresponding to the plurality of frames does not change in the imaging device.

8. The video display system according to claim 1 , wherein the imaging device, including a camera, sequentially generates the captured vide data, and sequentially outputs the display video data by quantizing the sequentially generated captured video data,

wherein an amount of variation of the second gradation value in the display apparatus correlates with a gradation value component smaller than the second gradation generated by the quantization.

9. The video display system according to claim 1 , wherein the imaging device performs operations including:

sequentially outputting quantized data obtained by quantizing input data based on the captured video data into the display video data,

sequentially storing the output quantized data into a storage,

sequentially calculating differences between the captured video data of the first gradation for a current frame and the quantized data for a previous frame stored in the storage, and

sequentially outputting integral data obtained by sequentially integrating the differences as the input data for quantizing.

10. The video display system according to claim 1 , wherein the imaging device performs operations including:

sequentially outputting quantized data obtained by quantizing input data based on the captured video data into the display video data,

sequentially storing the output quantized data into a storage,

sequentially outputting integral data obtained by sequentially integrating the quantized data stored in the storage, and

sequentially calculating differences between the captured video data of the first gradation and the integral data and sequentially outputting the calculated differences as the input data for quantizing.

11. The video display system according to claim 1 , wherein the imaging device performs operations including:

sequentially generating variation value data having the second bit number statistically or stochastically,

sequentially adding the variation value data to the captured video data of the first gradation, and

sequentially outputting quantized data obtained by quantizing data obtained by adding the variation value data to the captured video data into the display video data of the second gradation.

12. A video display method comprising:

sequentially generating captured video data of a first gradation having a first bit number sequentially inputted from an imaging element and sequentially outputting display video data of a second gradation having a second bit number smaller than the first bit number, based on the captured video data,

varying a second gradation value based on the second gradation of a predetermined pixel included in the display video data corresponding to a plurality of frames, when the plurality of frames continuous in time series are outputted to a display device based on the display video data, although a first gradation value based on the first gradation of the predetermined pixel included in the captured video data corresponding to the plurality of frames does not change.