Detector for detecting bad editing of image signal

Abstract

The device is in use for sensing TV image signal. When it is detected that source of TV image is from movie signal and not from video signal, deinterleaving process can be carried out for signal in movie mode by line multiplier directly in order to increase vertical resolution of TV image signal so that saw-toothed TV image caused by poor edited image signal will not create. The invention can detect poor edited image signal before it is played so as to prevent saw-toothed image created.

Description

technical field [0001] The present invention relates to a detection circuit, especially a detection device suitable for detecting whether there is bad editing of image signals. Background technique [0002] Due to the limitation of transmission bandwidth, the current transmission of TV images adopts the method of interactive transmission of odd / even image fields. As shown in FIG. 1 , odd fields 10 and 12 have only odd lines of image data, while even display fields 11 and 13 have only even lines of image data. Due to the improvement of the vertical resolution of the new generation TV, a line doubler (line doubler) is needed inside the TV to perform frequency doubling processing to improve the vertical resolution. Among them, the simplest frequency doubling process is to directly combine adjacent odd and even fields to form a progressive scan frame. However, since the adjacent odd and even fields have time differences, directly combining the odd and even fields to generate s...

AI Technical Summary

Problems solved by technology

[0008] Although the aforementioned method can effectively detect whether the image source is a film signal and achieve a perfect multiplier output, however, poor editing of the film data will cause damage to the 3:2 pull down ratio, resulting in jagged image output, as shown in the figure Fields 1-8 shown in 5 are from movie fragment A, while fields 9-16 are from movie fragment B. Due to the bad editing of movie fragment B, after field 9, it no longer conforms to the ratio of 3:2 pull down , and please refer to Fig. 4, since the film detection state transition diagram needs to be in the field 11 to judge the need to jump out of the film mode, therefore, when the output frame is generated based on the field 9, the original does not belong to the same Field 9 and Field 10 of the frame are combined into one frame, which will cause jaggedness in the TV image

[0009] In order to solve the aforementioned problems, US Patent 6201577 (name: Film source video detection) provides a method for detecting bad editing, which is to detect bad editing on the current output image, so as to notify the film detection when bad editing is found The editor jumps out of movie mode to avoid the problem of combining images that do not belong to the same frame into one frame. However, since the detection of bad edits is performed on the current output image, when bad edits are detected , the line multiplier already outputs an aliased frame, and it is not possible to completely avoid image aliasing

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