JPH04165765A - Picture storage device - Google Patents

Abstract

PURPOSE:To store the amount of data less than the amount of data of original data by converting a photograph and a picture into pseudo halftone by an image input device encoding them with an encoder and selecting the data with shorter data length with a data length comparing device to turned to be data storing image information. CONSTITUTION:An image input device 11 converts the photograph and picture into a digital electric signal, further, converts them into pseudo halftone by a dither method so as to express the gradation by binary. This pseudo halftone signal is inputted to an input buffer 121 of an MH encoder 12. An encoding part 120 reads out data from the input buffer 121 to be encoded by a run length method, and stores encoding data in an output buffer 122. A data length comparing device 13 compares the data length of the data stored in the input buffer 121 with the data length of the encoding data of the original data stored in the output buffer 122, and decides the data with shorter data length as data to be stored. Thus, the storage can be performed by the encoding to the amount of data not exceeding the amount of data of the original image.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image storage device used in personal computers, workstations, word processors, and the like.

Conventional technology In recent years, the number of applied devices for image storage devices has increased.

Conventionally, in this type of image storage method, since the amount of data read by an image input device is enormous, an encoder is provided to convert the read data into MH and MR.

The data is encoded using a run-length encoding method such as MMR, and the amount of data is compressed and stored.

FIG. 3 is a block diagram showing the configuration of a conventional image storage device. In the figure, numeral 31 is an image input device, which converts a photograph or picture to be read into a digital electrical signal, and is connected to an encoder 32.

The encoder 32 encodes the original data and sends the encoded data to the storage device 33 to store image data.

The operation of the conventional image storage device having the above configuration will be explained. In Figure 3, photos and pictures are input to the image input device 3.
1 into a digital electrical signal and input it to the encoder 32. The encoder 32 performs MH encoding, for example. M.H.
The encoded data is sent to the storage device 33 and stored therein. Storage devices include random access and static memories, hard disk drives, floppy disk drives, and the like.

Problems to be Solved by the Invention However, in such conventional image storage devices, a distributed dither method, a concentrated dither method, etc. are used to express a photograph with gradations in binary format in an image input device. Convert to halftone data. This pseudo-halftone data has a pattern of combinations of 0 and 1 periodically, so when run-length encoding is performed, the amount of encoded data becomes larger than the original data, which defeats the purpose of encoding. The problem was that it could not be achieved.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an image storage method that can encode and store an amount of data that does not exceed the amount of data of the original image.

Means for Solving the Problems In order to achieve the above object, the present invention provides an image input device that inputs an image and outputs image data including pseudo halftones, and an image input device that inputs the image data and outputs encoded data. An image comprising an encoder for outputting, a data length comparison means for comparing the data lengths of the image data and the encoded data and outputting the shorter data, and a data storage means for accumulating the output data of the comparison means. Use it as a storage device.

Effect of the Invention With the above configuration, the data length comparison means compares the data lengths of the image data before encoding and the encoded data after encoding, and selects the shorter data as the stored data.

Embodiment FIG. 1 is a block diagram showing the configuration of an image storage device according to an embodiment of the present invention. In the figure, 11 is an image input device having a pseudo halftone processing means, and an MH encoder 1
Connected to 2. The MH encoder 12 is connected to a data length comparator 13. The MH encoder 12 includes a large power buffer 121 that stores one line of original data received from the image input device 11, an encoding unit 120 that performs MH encoding on the data, and an output buffer 122 that stores one line of encoded data. It is configured. 14 is a storage device for storing data, and is connected to the data length comparator 13. The operation of the above configuration will be explained. The image input device 11 converts a photograph or picture into a digital electrical signal, and further converts it into a pseudo halftone using a dither method in order to express the gradation in binary. Conversion to pseudo halftones is well known and will therefore be omitted here. This pseudo halftone signal is input to the input buffer 121 of the MH encoder 12. The encoding unit 120 reads data from the input buffer 121, encodes it using a run-length method, for example, the MH encoding method, and stores the encoded data in the output buffer 122. The data length comparator 13 is connected to the input buffer 12.
1 and the data length of the encoded data of the original data stored in the output buffer 122, and the data with the shorter data length is determined as the data to be stored. Comparison of data length is performed using counter 13.
1 and a counter 132 measure the number of bits of data constituting one line, and a comparator 133 compares the measurement results. The comparator 133 outputs "1" when the original data is short, and outputs "O" when the encoded data is short. The output data switch 134 switches between original data and encoded data based on the output of the comparator 133. The data length comparator 13 causes the storage device 14 to store data with a short data length from the measurement results. At this time, the output data of the comparator 133 is added as an identification code indicating whether the data stored as information for decoding is original data or encoded data, and the data is stored in the storage device 14.

FIG. 2 is a schematic diagram showing the arrangement of stored information in an image storage device according to an embodiment of the present invention. In the figure, 21 is an identification code bit, and 22 is one line of data to be accumulated. When the identification code bit 21 is "1", it indicates original data, and when it is "0", it indicates encoded data.

According to the image storage device of the above embodiment, a photograph or picture is converted into pseudo halftone by the image input device having pseudo halftone processing means, MH encoding is performed by the MH encoder, and the data length is compared. Optimized data can be stored line by line by selecting the shorter data length on the device as the data to be stored in the image information, and the amount of data that is less than the amount of original data can be stored. .

Effects of the Invention As is clear from the above embodiments, the present invention provides an image input device that inputs an image and outputs image data including pseudo halftones, and an image input device that inputs the image data and outputs encoded data. An image storage device comprising an encoder, data length comparison means for comparing data tones of the image data and encoded data and outputting the shorter data, and data storage means for accumulating output data of the comparison means. By doing this, the data to be stored is coded without having a longer data length than the original image data, and the storage capacity of the data storage device can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an image storage device according to an embodiment of the present invention, FIG. 2 is a schematic diagram showing the structure of accumulated data in the image storage device according to an embodiment of the invention, and FIG. 3 is a conventional 1 is a block diagram showing the configuration of an image storage device of FIG. 11... Image input device, 12...
Encoder, 13...Data length comparison means, 14...
...Data storage means. Name of agent: Patent attorney Haruaki Koebi (2 persons) Figure 2 Figure 3

Claims (1)

[Claims] An image input device that inputs an image and outputs image data including pseudo halftones, an encoder that inputs the image data and outputs encoded data, and compares data lengths of the image data and encoded data. An image storage device comprising: data length comparison means for outputting shorter data; and data storage means for storing output data of said comparison means.