Image capture device and method for controlling image capture device

Abstract

To provide an imaging device capable of outputting image data on which a watermark image is superposed without missing part or all of the watermark image even when the image data is output by cutting out part of a frame of image data captured by an imaging unit.SOLUTION: An imaging unit 11 photographs a subject and generates first photographic image data composed of frames having a first angle of view. An image data holding unit 12 holds the first photographic image data. A distribution photographic image processing unit 31 generates second photographic image data by executing clipping processing of cutting out part of each frame of the first photographic image data read by the image data holding unit 12. A watermark image superimposing unit 32 generates photographic image data for output by superimposing a watermark image on a frame of second photographic image data. An output unit 35 outputs the photographic image data for output to the outside.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an imaging apparatus and a control method for the imaging apparatus. [Background technology]

[0002] An imaging device may superimpose a watermark image onto video data captured by an imaging unit, and record the superimposed image onto a recording medium or distribute the superimposed image over a network (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-328747 A Summary of the Invention [Problem to be solved by the invention]

[0004] With the recent spread of smartphones and high-speed, large-capacity communication lines, video data with a watermark image superimposed may be received and displayed by a smartphone. The aspect ratio of video data captured by an imaging device is usually 16:9. Smartphones often have small displays and do not have an aspect ratio of 16:9. Smartphones may also display the delivered video data on a vertically long display.

[0005] Therefore, in order to improve visibility on a smartphone display, it is conceivable to cut out a part of each frame of video data on which a watermark image is superimposed for distribution. However, when a part of each frame of video data is cut out to generate video data for distribution, the watermark image may be partially missing or completely lost. Here, distribution of video data is used as an example, but the same applies when distributing still image data.

[0006] The present invention aims to provide an imaging device and a control method for an imaging device that can output image data with a watermark image superimposed thereon without any loss of part of the watermark image or the entirety of the watermark image, even when outputting image data that is a portion of a frame of image data captured by an imaging unit. [Means for solving the problem]

[0007] The present invention includes an imaging unit that captures an image of a subject and generates first captured image data composed of frames having a first angle of view, an image data storage unit that stores the first captured image data, a captured image processing unit that performs clipping processing to cut out a portion of each frame of the first captured image data read from the image data storage unit and generates second captured image data, a first watermark image superimposing unit that generates output captured image data by superimposing a watermark image on the frames of the second captured image data, and an output unit that outputs the output captured image data to an external device. a second watermark image superimposing unit that generates photographed image data for recording by superimposing the watermark image on a frame of the first photographed image data read from the image data storage unit; and a recording processing unit that processes the photographed image data for recording so as to record the photographed image data for recording on a recording medium. The present invention provides an imaging device comprising:

[0008] In the present invention, an imaging section captures an image of a subject to generate first captured image data constituted by frames having a first angle of view, an image data storage section stores the first captured image data, a captured image processing section executes clipping processing to cut out a part of each frame of the first captured image data read from the image data storage section to generate second captured image data, a watermark image superimposing section superimposes a watermark image on a frame of the second captured image data to generate captured image data for output, and an output section outputs the captured image data for output to an external device. a second watermark image superimposing unit superimposes the watermark image on a frame of the first photographed image data read from the image data storage unit to generate photographed image data for recording, and a recording processing unit processes the photographed image data for recording to be recorded on a recording medium. A method for controlling an imaging device is provided. Effect of the Invention

[0009] According to the imaging device and imaging device control method of the present invention, even when image data that is cut out from a portion of a frame of image data captured by the imaging unit is output, it is possible to output image data with a watermark image superimposed thereon without any part of the watermark image being lost or being lost entirely. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing an imaging apparatus according to an embodiment; [Diagram 2] FIG. 13 is a diagram conceptually illustrating an alpha channel set for a watermark image. [Diagram 3] 2 is a diagram showing one frame of photographed image data D12 read out from the image data storage unit 12 appearing in FIG. [Figure 4] 2 is a diagram showing one frame of the captured image data for recording D22 on which the watermark image Wm has been superimposed by the watermark image superimposing section 220 in FIG. [Diagram 5] 1. FIG. 4 is a diagram showing clipping processing in which the distribution captured image processing unit 31 in FIG. 1 cuts out a part of each frame of the captured image data D12. [Figure 6] 6 is a diagram showing one frame of captured image data D31 for distribution obtained as a result of the clipping process shown in FIG. 5. FIG. [Figure 7] 2 is a diagram showing one frame of captured image data D32 for distribution on which a watermark image Wm has been superimposed by the watermark image superimposing unit 32 in FIG. [Figure 8] FIG. 13 is a partial enlarged view showing an example in which the difference in brightness between the background of the frame on which the watermark image Wm is superimposed and the mark Wm01 is smaller than a predetermined value. [Figure 9] FIG. 13 is a partial enlarged view showing a state in which the luminance of the mark Wm01 is inverted when the difference in luminance between the mark Wm01 and the background of the frame on which the watermark image Wm is superimposed is smaller than a predetermined value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] An image pickup apparatus and a control method for the image pickup apparatus according to an embodiment will be described below with reference to the accompanying drawings.

[0012] In Fig. 1, the imaging unit 11 includes an imaging element and a plurality of lenses, and captures an object with an angle of view (first angle of view) of, for example, an aspect ratio of 16:9 to generate captured image data (first captured image data). The imaging element may be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The image data storage unit 12 temporarily stores the captured image data output from the imaging unit 11. The image data storage unit 12 is a frame memory, and may be a synchronous dynamic random access memory (SDRAM) or a double-data-rate SDRAM (DDR).

[0013] The watermark image storage unit 21 stores watermark image data to be superimposed on the captured image data. The watermark image storage unit 21 is composed of a non-volatile memory. The watermark image data is composed of image data in a format having auxiliary data called an alpha channel that sets the opacity of the image. As an example, the watermark image data is in PNG format.

[0014] Fig. 2 conceptually shows the alpha channel set for the watermark image Wm indicated by the watermark image data. As an example, the background Wm00 in a rectangular area is set to 0% opacity (i.e., 100% transparency), and the mark Wm01 is set to 100% opacity (i.e., 0% transparency). In the example shown in Fig. 2, the mark Wm01 is the characters "W.MK."

[0015] The record-use captured image processing unit 22 performs at least one of scaling and noise reduction processing for a record-use captured image on the captured image data D12 read out from the image data storage unit 12. FIG. 3 shows one frame of the captured image data D12 read out from the image data storage unit 12.

[0016] As an example of scaling processing, when the captured image data output from the imaging unit 11 has a horizontal pixel count x vertical pixel count of 3840 x 2160, called 4K, the record captured image processing unit 22 reduces the pixel count to full HD 1920 x 1080. When the capacity of the recording medium 24 is sufficiently large, the record captured image processing unit 22 does not need to reduce the captured image data.

[0017] The record captured image processing unit 22 includes a watermark image superimposing unit 220 (second watermark image superimposing unit) that superimposes watermark image data on the captured image data D12. The watermark image superimposing unit 220 superimposes the watermark image data read from the watermark image storage unit 21 on the captured image data D12. Fig. 4 shows one frame of the record captured image data D22 on which the watermark image Wm has been superimposed by the watermark image superimposing unit 220.

[0018] Because the background Wm00 is set to 0% opacity by the α channel, only the mark Wm01 with 100% opacity appears to be superimposed on the captured image data D12. The watermark image superimposing unit 220 may automatically determine the position at which to superimpose the watermark image Wm on the captured image data D12, or may set the position at which to superimpose the watermark image Wm based on instruction data specified by the user.

[0019] The recording processing unit 23 encodes the recording captured image data D22 and files it as necessary in order to record the recording captured image data D22 on the recording medium 24. The recording processing unit 23 records the encoded recording captured image data D22 on the recording medium 24. The recording medium 24 is any recording medium, and may be a memory card constituted by a flash memory or a hard disk drive.

[0020] The captured image processing unit for distribution 31 generates captured image data for distribution D31 (second captured image data) by executing clipping processing to cut out a part of each frame of the captured image data D12 read out from the image data storage unit 12. As shown in Fig. 5, when the captured image processing unit for distribution 31 executes clipping processing to cut out a rectangular area indicated by a dashed line in a frame of the captured image data D12, a frame of the captured image data for distribution D31 having an angle of view (second angle of view) shown in Fig. 6 is generated.

[0021] The angle of view of the captured image data for distribution D31 has an aspect ratio different from the aspect ratio of 16:9. However, the angle of view of the captured image data for distribution D31 may have an aspect ratio of 16:9.

[0022] The delivery-purpose captured image processing unit 31 may execute a scaling process to reduce the number of lines and the number of pixels in addition to the clipping process. The degree of reduction in the number of lines and the number of pixels in the scaling process by the delivery-purpose captured image processing unit 31 may be greater than the degree of reduction in the number of lines and the number of pixels in the scaling process by the recording-purpose captured image processing unit 22.

[0023] The watermark image storage unit 33 stores watermark image data to be superimposed on the captured image data for distribution D31. The watermark image storage unit 33 is composed of a non-volatile memory. Like the watermark image data stored in the watermark image storage unit 21, the watermark image data stored in the watermark image storage unit 33 is also composed of image data in a format having an α channel.

[0024] 1, the watermark image storage unit 21 and the watermark image storage unit 33 are separate entities, but the watermark image storage unit 21 and the watermark image storage unit 33 may be configured as one common watermark image storage unit. The watermark image data to be superimposed on the photographed image data D12 and the watermark image data to be superimposed on the photographed image data for distribution D31 may be the same image data. The watermark image Wm to be superimposed on the photographed image data for distribution D31 may be smaller than the watermark image Wm to be superimposed on the photographed image data D12.

[0025] The watermark image superimposing unit 32 (first watermark image superimposing unit) superimposes the watermark image data read from the watermark image storage unit 33 onto the captured image data for distribution D31. Fig. 7 shows one frame of the captured image data for distribution D32 (captured image data for output) on which the watermark image Wm is superimposed by the watermark image superimposing unit 32.

[0026] Similarly, the watermark image Wm superimposed on the captured image data for distribution D31 has a background Wm00 set to 0% opacity by the alpha channel, so that only the mark Wm01 with 100% opacity appears to be superimposed on the captured image data for distribution D31. The watermark image superimposing unit 32 may automatically determine the position at which to superimpose the watermark image data on the captured image data for distribution D31, or may set the position at which to superimpose the watermark image data based on instruction data instructed by the user.

[0027] The output processing unit 34 encodes the photographed image data for distribution D32, performs protocol packetization processing and SDI (Serial Digital Interface) serialization processing as necessary, and supplies the data to the output unit 35. The output unit 35 outputs the encoded photographed image data for distribution D32 supplied from the output processing unit 34 to a network outside the imaging device. The image data distributed via the network is equivalent to the photographed image data for distribution D32 shown in FIG.

[0028] However, when the watermark image superimposing unit 220 superimposes the watermark image data on the photographed image data D12, depending on the relationship between the luminance of the background on which the watermark image Wm is superimposed and the luminance of the mark Wm01, the mark Wm01 may be difficult to see. For example, suppose that the photographed image data D12 is 8 bits, the background on which the watermark image Wm is superimposed has a gradation value of 255, which is the maximum luminance, and the mark Wm01 has a gradation value of 0, which is the minimum luminance. In this case, the mark Wm01 is easily visible.

[0029] 8, the background on which the watermark image Wm is superimposed has a low gradation, for example, a gradation value of 30, and the mark Wm01 has the lowest luminance, a gradation value of 0. In this case, the luminance difference between the background and the mark Wm01 is small, so the mark Wm01 cannot be clearly seen.

[0030] Therefore, when the difference in brightness between the mark Wm01 and the background on which the watermark image Wm is superimposed is smaller than a predetermined value in each frame of the captured image data D12, the watermark image superimposing unit 220 inverts the brightness (black and white) of the mark Wm01. As shown in Fig. 9, when the mark Wm01 has a gradation value of 0, the watermark image superimposing unit 220 converts the watermark image Wm to a gradation value of 255 and superimposes the watermark image Wm on the frame of the captured image data D12.

[0031] The same applies when the watermark image superimposing unit 32 superimposes the watermark image data on the photographed image data for distribution D31. For distribution In each frame of the captured image data D31, when the difference in luminance between the background on which the watermark image Wm is superimposed and the mark Wm01 is smaller than a predetermined value, the luminance (black and white) of the mark Wm01 is inverted.

[0032] There are cases where the color of the watermark image Wm (mark Wm01) is strictly specified, such as a company logo, and it is impossible to invert the brightness of the mark Wm01. In this case, the watermark image superimposing units 220 and 32 may set in advance that inversion of the brightness of the mark Wm01 is impossible, or may set a flag indicating whether or not inversion is possible in the watermark image data, and decide whether or not to invert the mark Wm01 depending on whether or not the flag indicates whether or not inversion is possible. The watermark image superimposing units 220 and 32 may set whether or not to invert the brightness of the mark Wm01 based on instruction data instructed by the user.

[0033] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention. [Explanation of symbols]

[0034] 11 Imaging unit 12 Image data storage unit 21 Watermark image storage unit 22 Recording image processing section 23 Recording processing section 24 Recording media 31 Distribution image capture processing unit 32 Watermark image overlay section 33 Watermark image storage unit 34 Output Processing Section 35 Output section 220 Watermark image overlay section

Claims

1. an imaging unit that captures an image of a subject and generates first captured image data configured of a frame having a first angle of view; an image data storage unit that stores the first captured image data; a captured image processing unit that performs clipping processing to cut out a part of each frame of the first captured image data read from the image data storage unit, to generate second captured image data; a first watermark image superimposing unit for generating output photographed image data by superimposing a watermark image on a frame of the second photographed image data; an output unit that outputs the captured image data for output to an external device; a second watermark image superimposing unit that generates recording photographic image data by superimposing the watermark image on a frame of the first photographic image data read from the image data storage unit; a recording processing unit that processes the photographed image data for recording so as to record the photographed image data on a recording medium; An imaging device comprising:

2. 2. The imaging device according to claim 1, wherein the first watermark image superimposing unit inverts a luminance of the watermark image when a luminance difference between the background and the watermark image in a frame of the second captured image data on which the watermark image is superimposed is smaller than a predetermined value.

3. An imaging device as described in claim 1 or 2, wherein the second watermark image superimposition unit inverts the brightness of the watermark image when the brightness difference between the background and the watermark image in a frame of the first captured image data on which the watermark image is superimposed is smaller than a predetermined value.

4. an imaging unit captures an image of a subject and generates first captured image data configured of a frame having a first angle of view; an image data storage unit stores the first captured image data; a captured image processing unit performs a clipping process to cut out a part of each frame of the first captured image data read from the image data storage unit, thereby generating second captured image data; a watermark image superimposing unit superimposing a watermark image on a frame of the second captured image data to generate captured image data for output; An output unit outputs the captured image data for output to an outside. a second watermark image superimposing unit superimposing the watermark image on a frame of the first photographed image data read from the image data storage unit to generate photographed image data for recording; A recording processing unit processes the recording photographic image data so as to record the data on a recording medium. A method for controlling an imaging device.

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