JP2009165158A - Moving image recording device, electronic camera device, moving image recording method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving image recording device and electronic camera device capable of recording moving images with uniform image quality until the termination of moving image photographing, and a moving image recording method. <P>SOLUTION: During a moving image recording operation, a frame rate and a bit rate are stored when a time period used for write-processing of image data for each frame on a recording medium is beyond the limit, exceeding the time period permitted at that time. When the processing time period is beyond the limit, the frame rate and bit rate are reduced in the next moving image recording by a predetermined ratio. For example, when the processing time period is beyond the limit, the frame rate and bit rate are reduced according to the excess ratio of the processing time period beyond the limit with respect to the permitted time period. This enables continuous recording of moving images without deteriorating the image quality during recording thereof. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a moving image recording device and an electronic camera device having a function of recording moving images in a stream, a moving image recording method, and a program.

  Conventionally, Motion JPEG (Joint Photographic coding Experts Group), MPEG (Moving Picture coding Experts Group), etc. have been used as the data format for recording moving images in digital cameras and mobile phones equipped with video shooting functions. Yes. These are formats for recording image data that is compression-coded at regular time intervals. As a medium for recording a moving image, an SD memory card (Serure Digital memory card) or the like is often used.

  When recording a moving image, for moving image shooting within a specified time, image data that has been compression-coded at regular time intervals is temporarily stored in the internal memory, and the moving image data is written to the recording medium after shooting. There is no time restriction in the writing process. On the other hand, for moving image shooting (hereinafter referred to as stream recording) capable of shooting up to the full capacity of the recording medium, moving image data that has been shot and compression-encoded must be sequentially written to the recording medium. There are some restrictions.

  On the other hand, the data writing performance of the memory card differs depending on the memory card, and there are a card with a fast writing and a card with a slow writing. For this reason, when a card with slow writing is used, it may take a long time to write, and a situation may occur in which a series of processing does not end within a fixed time allowed for processing one image. In that case, by reducing the image quality, such as stopping shooting, reducing the frame rate (increasing the interval between recorded images), or decreasing the bit rate (increasing the compression rate of the recorded images) In general, countermeasures such as continuing shooting by reducing the amount of data written to the memory card are performed.

  Also, for example, in Patent Document 1 below, in a digital camera, a buffer area for a plurality of frames is secured in the internal memory in advance, and when moving images are stream-recorded, moving image data that has been shot and compressed and encoded is recorded. In parallel with the write operation to the internal memory, the previously stored image data is read and recorded on a memory card, etc., and the recorded video data is erased from the internal memory. In other words, the internal memory is used as a ring buffer. A moving image recording method is described in which the moving image recording is stopped when the ring buffer becomes full of moving image data not recorded on the memory card as the shooting time elapses.

JP 2000-232619 A

  However, in the case of the conventional method described above, if a video card is shot many times using a memory card with a slow writing speed or a memory card with a slow writing speed, the shot is taken during the shooting each time a video is shot. There is a problem that the image is forcibly canceled or the image quality changes during shooting, and a moving image with uniform image quality cannot be obtained from the start of shooting a movie to the end of shooting.

  The present invention has been made in view of such a conventional problem, and a moving image recording apparatus, an electronic camera device, and a moving image recording method capable of recording a moving image with uniform image quality until shooting of the moving image is completed. And it aims at providing the program used for those realization.

  In order to solve the above-mentioned problem, in the invention of claim 1, moving image recording means for sequentially recording image data constituting a moving image on a recording medium while performing image processing at a predetermined frame period, and the moving image recording means Determining means for determining whether or not there has been a delay that hinders normal recording of moving images in the writing process of the image data after the image processing to the recording medium, and the determination means determines that the delay has occurred. Information storage means for storing information indicating that, and the image quality of the moving image recorded in the next recording operation by the moving image recording means based on the information stored in the information storage means A moving image recording apparatus provided with image quality setting means for setting

  In such a configuration, when there is a delay that hinders normal recording of moving images in the writing processing of image data after image processing to the recording medium during recording of moving images, information indicating that is stored. Based on the information, the image quality of the moving image to be recorded in the next recording operation is automatically set. Accordingly, during the recording of a moving image, if there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium, the moving image to be recorded in the subsequent recording operation It is possible to make the image quality lower than the image quality when the delay occurs.

  According to a second aspect of the present invention, the information storage means determines the image quality of the moving images sequentially recorded on the recording medium by the moving image recording means when the determining means determines that a delay has occurred. The image quality setting means stores the image quality of the moving image recorded in the next recording operation by the moving image recording means more than the image quality indicated by the image quality information stored in the information storage means. The image quality is set to be lower by a predetermined ratio.

  In such a configuration, during the recording of a moving image, if there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium, the recording operation is performed in the subsequent recording operation. It is possible to set the image quality of the moving image to be lower by a predetermined ratio than the image quality when the delay occurs.

  According to a third aspect of the present invention, when the information storage means determines that a delay has occurred by the determination means, the image quality of the moving image recorded in the next recording operation by the moving image recording means The image quality setting means sets the image quality of the moving image recorded in the next recording operation by the moving image recording means to the image quality indicated by the image quality information stored in the information storage means. It was supposed to be set.

  In such a configuration, during the recording of a moving image, if there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium, the recording operation is performed in the subsequent recording operation. It is possible to set the image quality of the moving image to be lower than the image quality when the delay occurs, which is indicated by the image quality information stored when the delay occurs.

  According to a fourth aspect of the present invention, the image processing apparatus includes a measuring unit that measures a time required when the image data after image processing is recorded on the recording medium by the moving image recording unit, and the image quality setting unit includes: The image quality of the moving image recorded in the next recording operation by the moving image recording unit is determined according to the time required by the measuring unit during the recording of the moving image when the determination unit determines that the delay has occurred. The image quality is set to be lowered by a rate corresponding to the excess rate with respect to the time allowed for the recording of the image data after the image processing.

  In such a configuration, during the recording of the moving image, the image quality of the moving image recorded in the recording operation after a delay that hinders normal recording of the moving image occurs in the writing process of the image data after the image processing to the recording medium. The amount of lowering can be minimized.

  The invention according to claim 5 further includes a buffer memory for temporarily storing image data after image processing for a plurality of frames to be recorded on the recording medium, wherein the determination means writes image data in the buffer memory. It is determined that the delay has occurred when the position and the read position are in a predetermined relationship, and the image quality setting means determines the image quality of the moving image recorded in the next recording operation by the moving image recording means. According to the ratio between the total size of image data not recorded on the recording medium recorded in the buffer memory and the total size of image data recorded on the recording medium when it is determined that the delay has occurred. The image quality was set to be reduced by a certain percentage.

  Even in such a configuration, during the recording of the moving image, the image quality of the moving image recorded in the recording operation after a delay that hinders the normal recording of the moving image occurs in the writing process of the image data after the image processing to the recording medium. The amount of lowering can be minimized.

  According to a sixth aspect of the present invention, there is provided a measuring means for measuring a time required for recording image data after image processing by the moving image recording means to the recording medium, and a moving image by the moving image recording means. Speed calculating means for calculating the average writing speed of data to the recording medium from the total required time measured by the measuring means during image recording and the total size of all image data recorded on the recording medium; Each time a new moving image is recorded on the recording medium by the moving image recording unit, a speed history storage unit that stores the average writing speed calculated by the calculation unit as history information, and the speed history storage unit stores the average writing speed. Acquisition means for acquiring the degree of deterioration of the average writing speed in a predetermined period, and the degree of deterioration acquired by the acquisition means are determined based on the history information that is obtained. It was that a notification means for notifying that exceeds the degree of deterioration.

  In such a configuration, when the writing performance of data on the recording medium deteriorates by a certain level due to fragmentation of image data to be recorded as the usage period elapses, it can be recognized by the user.

  According to a seventh aspect of the present invention, in the moving image recording method for sequentially recording the image data constituting the moving image on the recording medium while performing image processing at a predetermined frame period, the image data after the image processing on the recording medium is performed. A step of determining whether or not a delay that hinders normal recording of moving images has occurred in the writing process of the image data; and a step of storing information indicating that when it is determined that the delay has occurred; And setting the image quality of the moving image to be recorded prior to the next moving image recording operation based on the stored information.

  Accordingly, during the recording of a moving image, if there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium, the moving image to be recorded in the subsequent recording operation It is possible to make the image quality lower than the image quality when the delay occurs.

  According to the eighth aspect of the present invention, there is provided a computer having a moving image recording apparatus that sequentially records image data constituting a moving image on a recording medium while performing image processing on a predetermined frame period. A moving image recording unit that sequentially records data on a recording medium while performing image processing at a predetermined frame period, and a writing process of image data after image processing on the recording medium by the moving image recording unit A determination unit that determines whether or not a delay that inhibits recording has occurred; a control unit that stores information indicating the fact in the information storage unit when the determination unit determines that the delay has occurred; and the information Based on the information stored in the storage means, it functions as an image quality setting means for setting the image quality of a moving image recorded in the next recording operation by the moving image recording means. It was because of the program.

  According to the ninth aspect of the present invention, the image data constituting the moving image captured at a predetermined frame period by the imaging unit is sequentially recorded on a removable recording medium while being compressed at the predetermined frame period. In an electronic camera device having a moving image shooting function, moving image recording means for sequentially recording image data constituting a moving image on a recording medium while performing image processing at a predetermined frame period, and to the recording medium by the moving image recording means A determination means for determining whether or not a delay that hinders normal recording of moving images has occurred in the writing process of the image data after the image processing, and when it is determined by the determination means that the delay has occurred, Control means for storing information indicating the effect in the information storage means, and the next recording operation by the moving image recording means based on the information stored in the information storage means And an electronic camera apparatus and a image quality setting means for setting the image quality of a moving image to be recorded.

  In such a configuration, if there is a delay that hinders normal recording of moving images in the writing processing of image data after image processing to the recording medium during recording of moving images composed of captured images, Information indicating this is stored, and the image quality of the moving image to be recorded in the next recording operation is automatically set based on the information. Accordingly, during the recording of a moving image, if there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium, the moving image to be recorded in the subsequent recording operation It is possible to make the image quality lower than the image quality when the delay occurs.

  In the apparatus and method of the present invention, during the recording of a moving image, if there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium, The image quality of the moving image recorded by the recording operation can be made lower than the image quality when the delay occurs (for example, lower by a predetermined ratio). Therefore, for example, when the same recording medium is used as a recording medium for recording a moving image, even if there is a delay in the writing process of the image data during recording of the moving image, the recording of the moving image from the next time onward is in progress. Therefore, the normal recording operation can be continued without changing the image quality, and a moving image can be recorded with a uniform image quality until the moving image shooting is completed.

  In addition, in the inventions of claims 4 and 5, during the recording of the moving image, there is a delay that hinders normal recording of the moving image in the writing process of the image data after the image processing to the recording medium. The reduction in image quality of moving images recorded by recording operations can be minimized. Therefore, a higher quality moving image can be recorded.

  Furthermore, in the invention of claim 6, when the writing performance of data in the recording medium deteriorates more than a certain amount due to fragmentation of the image data to be recorded as the usage period elapses, it can be recognized by the user. I did it. Therefore, by executing initialization of the recording medium, it is possible to maintain the quality of the recordable moving image as much as possible according to the original data writing performance of the recording medium.

It is a block diagram of a digital camera common to each embodiment of the present invention. It is a schematic diagram which shows the memory space of a built-in memory. It is a flowchart which shows the content of the video recording process in the embodiment. It is a flowchart following FIG. It is a flowchart which shows the content of pre-processing. It is a schematic diagram which shows write time history data. It is a schematic diagram which shows the content of recording information. It is a schematic diagram which shows the memory space of the built-in memory in 2nd Embodiment. It is a flowchart which shows the content of the video recording process in the embodiment. It is a flowchart which shows the content of pre-processing. It is a schematic diagram which shows the content of recording information.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a block diagram of a digital camera common to each embodiment of the present invention. This digital camera has a moving image shooting function and has the following configuration.

  The digital camera includes a camera body 1 and a recording medium 20 that can be attached to and detached from the camera body 1, and the camera body 1 receives an optical system 2 composed of a plurality of lenses, and receives light through the optical system 2. A CCD 3 mounted with a color filter such as a Bayer array, which is an imaging means for forming an optical image of a subject on the surface, is disposed. The CCD 3 is driven by a drive signal sent from the timing generator 7, photoelectrically converts the light image of the subject and outputs it as an imaging signal. The output signal from the CCD 3 is subjected to correlated double sampling and gain adjustment by the CDS circuit 4 and converted to a digital signal by the A / D conversion circuit 5. The A / D-converted Bayer data is input to the DSP unit 6 and subjected to processing such as pedestal clamping, and then converted into a luminance (Y) signal and a color difference (UV) signal by a luminance / color difference matrix circuit in the block. . Note that the DSP unit 6 also performs processing for improving image quality such as auto iris, auto white balance, contour enhancement, and pixel interpolation.

  The YUV data output from the DSP unit 6 is converted into a preset image size by the resolution conversion block 8, and then one frame worth of data is sequentially secured in the built-in memory 14 (for example, SDRAM). 14a (see FIG. 2). The YUV data for one frame stored in the built-in memory 14 is sent to the display controller 11 where it is converted into a video signal and then displayed as a through image on an LCD (liquid crystal display) 12. The LCD 12 also functions as a notification unit of the present invention at the time of moving image shooting described later.

  In addition, YUV data stored in the built-in memory 14 at the time of moving image shooting is sequentially sent to the data compression / decompression block 9, and after being compressed by a codec of a predetermined moving image recording method (for example, Motion-JPEG or MPEG), it is coded and embedded. After being temporarily stored in the memory 14, it is sequentially written to the recording medium 20 as frame data (video data) via the media controller 10. Such a series of operations is repeatedly executed for each frame. That is, stream recording is performed. The frame rate for moving image shooting is determined by the timing signal generated by the timing generator 7, and the compression rate of the encoded data is determined by the quantization table value in the data compression / decompression block 9. The YUV data for one frame stored in the built-in memory 14 at the time of still image shooting is encoded after being compressed by the data compression / decompression block 9 using the JPEG method or the like, and then filed in the built-in memory 14. The still image data (still image file) is recorded on the recording medium 20 via the media controller 10. The data compression / decompression block 9 decompresses still image data and moving image data read from the recording medium 20 during reproduction of a still image or moving image, and stores the image data work area in the built-in memory 14 as still image data or frame data. Expands to 14a.

  The voice processing block 15 converts voice input to the microphone 16 built in the camera body 1 during video recording with voice into a digital signal, and sends it to the built-in memory 14 as audio data after data compression. The audio data sent to the built-in memory 14 is sequentially written to the recording medium 20 as a series of stream data together with the frame data. The audio processing block 15 decodes the audio data sent from the built-in memory 14 and converts it into an analog audio signal at the time of reproducing the moving image with sound, and then outputs the sound from the built-in speaker 17 built in the camera body 1. Let

  The key input block 18 includes a plurality of operation keys such as a shutter button, a power key, and a MENU key, and outputs a key input signal corresponding to the key operation by the user to the CPU 13. The shutter button also functions as a recording start / end button when shooting a moving image.

  Each block described above is controlled by the CPU 13, and programs and data necessary for the CPU 13 to control each block are stored in the program memory 19. The CPU 13 operates based on the program and key input signals, thereby functioning as a moving image recording unit, a determination unit, an image quality setting unit, a measurement unit, a speed calculation unit, a control unit, and an acquisition unit of the present invention.

  The program memory 19 includes a rewritable non-volatile memory such as an EEPROM or a flash memory. In addition to the program and data, the program memory 19 is set by a user and setting data relating to each function, for example, a moving image recorded at the time of moving image shooting. Recording parameters such as an image size, a frame rate, and a compression rate that determine the quality of the image are stored as needed. Further, at the time of moving image shooting, as shown in FIG. 2, the built-in memory 14 has a general-purpose work area 14b used as a buffer for storing work data such as write information 100 (see FIG. 6) described later. Are secured separately from the image data work area 14a.

  Next, the operation according to the present invention in the digital camera having the above configuration will be described. FIG. 3 is a flowchart showing the contents of the moving image shooting process executed by the CPU 13 in response to the shooting start operation by the shutter button in the moving image shooting mode. Here, it is assumed that the moving image shooting mode is set for the first time after the start of use of the recording medium 20 or after initialization.

  When the photographing start operation is performed, the CPU 13 immediately proceeds to the pre-processing shown in FIG. 5 (step SA1), and confirms whether or not recording information 200 (see FIG. 7) described later is recorded on the recording medium 20 (see FIG. 7). Step SA101). Here, since no moving image recording has been performed on the recording medium 20 and the recording information 200 does not exist (NO in step SA101), the processing returns to the processing in FIG. 3 as it is, and the frame rate set by the user at that time, Video recording processing (stream recording) according to the image size and compression rate is started. Since there is no previous image data (frame data) at the imaging timing immediately after the start of imaging (both steps SA2 and SA3 are YES), imaging processing by the CCD 3 is immediately performed (step SA4). Subsequently, after compressing and encoding the captured first frame image data (step SA5), writing of the compressed and encoded image data to the recording medium 20 is started, and measurement of the image data writing time by the timer function is started. Start (step SA6).

  Thereafter, when the writing of the image data is finished (YES in step SA7), the writing time measurement is finished (step SA8), and the measurement result and the written data size are stored in the general-purpose work area 14b of the built-in memory 14 ( Step SA9). Until a shooting end operation or detection of the full state of the recording medium 20 (NO in step SA10), every time a new shooting timing arrives, imaging processing, compression encoding, and data writing to the recording medium 20 are performed. Are repeated (steps SA4 to SA9), during which the writing time (T1, T2, T3,...) For the number of frames per frame and the size of the written image data (D1, D2, D3) are written in the general-purpose work area 14b. ,..., And the write information 100 shown in FIG.

  Further, when any shooting timing arrives while the above processing is repeated, the writing process (storing process) to the recording medium 20 for the image data of the previous frame has not been completed (NO in step SA3). Then, “out of range” is temporarily stored as the processing time information in the general-purpose work area 14b (step SA11). In the general-purpose work area 14b, “within range” is stored in advance as an initial value of the processing time information. Further, by executing a process for using the image data of the previous frame instead of the image data of the current frame, the amount of data written to the recording medium 20 is reduced (step SA12), and the process returns to step SA2. .

  Eventually, if there is a shooting end operation by the user or the full state of the recording medium 20 is detected (YES in step SA10), the processing continues to the processing shown in FIG. 4 and the processing time information stored in the buffer memory is “out of range”. If not (NO in step SA13), the average writing speed is calculated from the total size of the written image data and the total writing time based on the writing information 100 stored in the buffer memory (step SA14). The calculation result, the processing time information (in this case “within range”), the set frame rate and the set bit rate at the time of shooting are recorded in a predetermined area of the recording medium 20 as recording information 200 as shown in FIG. (Step SA15), the moving image shooting process is terminated as it is. The set bit rate is a value that is uniquely determined by the frame rate, image size, and compression rate set by the user.

  If the processing time information stored in the buffer memory is “out of range” (YES in step SA13), the average writing speed is calculated in the same manner as described above (step SA16), and then the general-purpose work area 14b. The maximum writing time stored as the writing information 100, that is, the longest time required for writing the image data that was being written to the recording medium 20 when the imaging timing arrived, A ratio (excess ratio) with respect to the allowable writing time is calculated for an amount exceeding the writable time (imaging processing interval) of the image data at the frame rate (step SA17). Then, the calculation result, the processing time information (in this case, “out of range”), the set frame rate and set bit rate at the time of shooting, and the average writing speed are recorded as recording information 200 in a predetermined area of the recording medium 20 ( Step SA18).

  Next, it is confirmed whether or not the recording information 200 more than the prescribed number of times (in the following description, 100 times) is recorded on the recording medium 20 (step SA19). Here, it is the first moving image shooting after the recording medium 20 is initialized, and the recording information 200 is recorded only once (NO in step SA19), so the moving image shooting process is terminated. Note that the processing in the case where recording information more than the specified number of times has been recorded will be described later.

  On the other hand, when the second and subsequent moving image shootings are started, the previous recording information 200 is recorded on the recording medium 20 in the pre-processing of FIG. 5 described above (YES in step SA101). The previous recording information 200 is read (step SA102), and whether or not the previous processing time information is “out of range”, that is, whether or not there has been a delay in writing the image data to the recording medium 20 during the previous moving image shooting. (Step SA103). At this time, if the processing time information is “within range” and there is no delay (NO in step SA103), the pre-processing is immediately terminated, and a new moving image is obtained by the processing after step SA2 in FIG. Record.

  If the previous processing time information is “out of range”, the frame rate and bit rate values in the recording parameters at the time of the current video recording are set in correspondence with the processing time information. The frame rate and the bit rate are set to values corresponding to the corresponding excess ratio, that is, the image quality (frame rate, image size, compression rate, etc.) of the moving image is set in the recording medium 20. Setting is made to decrease according to the data writing performance (step SA104). For example, as shown in FIG. 7, when the previous (first) excess rate is 20%, the frame rate is 15 fps, and the bit rate is 100 Kbytes, the reduction rate is set to 80%, and the frame rate is set to Set 12fps and bit rate to 80K bytes. Thereafter, the pre-processing is terminated, and the processing after step SA2 in FIG. 3 is executed. As a result, at the time of the second moving image shooting, the process of using the previous image data in any frame without causing a delay in writing the image data to the recording medium 20 (the process of step SA12). It is possible to record a moving image with a uniform image quality (stream recording) until shooting is completed without causing a partial deterioration in image quality due to the execution.

On the other hand, when moving image shooting is performed a plurality of times by the above processing, recording information 200 for the number of shooting times is accumulated in a predetermined area in the recording medium 20 as shown in FIG. At the end of any moving image shooting, the processing time information stored in the general-purpose work area 14b is “out of range” (YES in step SA13), and is recorded in a predetermined area of the recording medium 20. When the number of recorded information 200 is recorded more than the specified number of times (100 times) including that time (YES in step SA19), the degree of deterioration of the average writing speed based on the recorded information 200, that is, the recording medium The degree of deterioration of the data writing performance at 20 is calculated (step SA20). Specifically, the ratio (percentage) of the current average write speed calculated in step SA16 to the oldest average write speed that is stored 100 times or more before this time and whose processing time information is “out of range” As the degree of deterioration,
Degree of degradation = oldest average writing speed ÷ current average writing speed × 100
Ask for.

  If the calculated degree of deterioration is not more than the specified value (NO in step SA21), the moving image shooting process is terminated, and if the degree of deterioration is more than the specified value (YES in step SA21), the initialization of the recording medium is prompted. After the message is displayed on the LCD 12 (step SA22), the moving image shooting process is terminated. For example, when the recording information recorded on the recording medium 20 has the contents shown in FIG. 7 and the specified deterioration degree is 80%, the processing time information is “out of range” this time, which is the 103rd time. In addition, since the average writing speed is 63 Kbytes / s and the degree of deterioration with respect to the first 83 Kbytes / s is 75%, a message prompting the initialization of the recording medium 20 is displayed on the LCD 12.

  As a result, when a device such as a flash memory is used as the recording medium 20, if the data writing performance deteriorates more than a certain amount due to fragmentation of the image data to be recorded as the usage period elapses, the user is made to recognize it. be able to. Therefore, by executing the initialization of the recording medium 20, it is possible to maintain the quality of the recordable moving image as much as possible according to the original data writing performance of the recording medium 20.

  In the present embodiment, when a delay occurs in the writing process of the image data to the recording medium 20 during moving image shooting, the image data of the previous frame is used instead of the image data of the current frame. Although the amount of data written to the medium 20 is reduced (step SA12), the moving image shooting may be stopped at that time. Even in such a case, at the next moving image shooting, a moving image can be recorded (stream recording) with uniform image quality until the shooting is completed. However, it is necessary to perform the recording process of the recording information 200 in steps SA14 to SA18 described above before ending the moving image shooting process.

  Further, when moving image shooting, there is a delay in the writing process of image data to the recording medium 20, and when lowering the frame rate and bit rate in the next moving image shooting, they are written in the allowable writing time of the writing time when the delay occurs. The frame rate and the bit rate may be decreased by a predetermined rate determined in advance, regardless of the excess rate. However, according to the present embodiment, the reduction rate of the frame rate and the bit rate can be minimized, and a higher quality moving image can be recorded at the next moving image shooting.

  In the present embodiment, the recording medium 20 functions as the information storage unit and the speed history recording unit of the present invention, and a plurality of pieces of recording information 200 acquired each time a moving image is taken are stored in the recording medium 20 as history information. However, as described above, the frame rate and the bit rate for the next moving image shooting are reduced by a predetermined ratio, and processing for prompting the user to initialize the recording medium 20 is performed. If not performed, only the recording information 200 at the time of the previous moving image shooting may be stored in the recording medium 20.

  The recording information 200 may be recorded not on the recording medium 20 but on the camera body (for example, the program memory 19). In that case, the recording information 200 is stored in association with the identification information for identifying the recording medium 20, and the recording information corresponding to the recording medium 20 (identification information) to be used is read and used. There is a need.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the present embodiment, in the digital camera having the same configuration as that shown in FIG. 1 in the first embodiment, the built-in memory 14 stores the image data work area 14a and the image data work area 14a as shown in FIG. Apart from the general-purpose work area 14b, a ring buffer area (for example, a size area capable of recording moving image data of about 60 seconds) 14c used as the ring buffer described above is allocated, and the built-in memory 14 is the present invention. And the program memory 19 causes the CPU 13 to perform a moving image shooting process described later, thereby causing the CPU 13 to function as a moving image recording unit, a determination unit, an image quality setting unit, and a control unit of the present invention. The program for recording is recorded.

  Hereinafter, the operation of the present embodiment according to the present invention will be described. FIG. 9 is a flowchart showing the contents of the moving image shooting process executed by the CPU 13 in response to the shooting start operation by the shutter button in the moving image shooting mode. In this case as well, it is assumed that the moving image shooting mode is set for the first time after the start of use of the recording medium 20 or after initialization.

  When there is a shooting start operation, the CPU 13 immediately proceeds to the pre-processing shown in FIG. 10 (step SB1), and checks whether or not recording information to be described later is recorded on the recording medium 20 (step SB101). Here, since moving image recording has never been performed on the recording medium 20 and recording information does not exist (NO in step SB101), the processing returns to the processing of FIG. 9 as it is, and the frame rate and image set by the user at that time Video recording processing (stream recording) according to the size and compression rate is started. At the imaging timing immediately after the start of imaging, the ring buffer area 14c of the built-in memory 14 is empty (steps SB2 and SB3 are both YES), so the imaging processing by the CCD 3 is immediately performed (step SB4). Subsequently, after the image data of the captured first frame is compressed and encoded (step SB5), the compressed and encoded image data is stored in the ring buffer area 14c (step SB6).

  Thereafter, until a shooting end operation is performed (NO in step SB7), the imaging process, compression encoding, and data storage in the ring buffer area 14c are repeated each time a new shooting timing arrives (steps SB4 to SB6). ). In the meantime, the image data stored in the ring buffer area 14c is read out in the storage order and recorded on the recording medium 20 as needed, and the moving image data that has been recorded is erased from the ring buffer area 14c (overwriting is permitted). (Processing) is performed in parallel (not shown).

  Further, when any shooting timing arrives while the above processing is repeated, if there is not enough space in the ring buffer area 14c to store the next image data (NO in step SB3), the ring The buffer state is “full” and the data amount already written in the recording medium 20 at that time is temporarily stored in the buffer (general-purpose work area 14b) (step SB8). In the general-purpose work area 14b, “available” is stored in advance as a ring buffer state. Further, by executing a process for using the image data of the previous frame in place of the image data of the current frame, the amount of data written to the recording medium 20 is reduced (step SB9), and the process returns to step SB2.

  Eventually, if there is a shooting end operation by the user or the full state of the recording medium 20 is detected (YES in step SB7), the ring buffer state stored in the buffer memory, the amount of written data, the frame rate at the time of shooting, After recording in a predetermined area of the recording medium 20 as recording information 300 (see FIG. 11) including the bit rate (step SB10), the moving image shooting process is terminated.

  On the other hand, when the second and subsequent moving image shootings are started, the recording information is recorded on the recording medium 20 in the above-described pre-processing of FIG. 10 (YES in step SB101). Reading (step SB102), it is confirmed whether or not the ring buffer state is “full” (step SB103). At this time, if the ring buffer state is “available” (NO in step SB103), the preliminary processing is immediately terminated, and a new moving image is recorded by the processing after step SB2 in FIG.

  On the contrary, when the recording information 300 has the contents as shown in FIG. 11 and the ring buffer state is “full”, the frame rate and bit rate values in the recording parameters at the time of the current video recording are In accordance with the ratio of the written data amount recorded together with the buffer state and the ring buffer capacity, the previously set frame rate and bit rate are set to lower values, that is, the image quality of the moving image is set in the recording medium 20. Setting is made to decrease according to the data writing performance (step SB104).

  For example, in the illustrated example, the previously set frame rate is 15 fps, the bit rate is 100 Kbytes, and the amount of written data is 48000 Kbytes. Therefore, if the ring buffer capacity is 6000 Kbytes (ratio is 8: 1) The rate of reduction is set to 80%, the frame rate is set to 12 fps, and the bit rate (image size, compression rate) is set to 80 Kbytes. Thereafter, the pre-processing is terminated, and the processing from step SB2 onward in FIG. 9 is executed. Thereby, at the time of the second moving image shooting, the ring buffer does not overflow during the moving image shooting, that is, a portion obtained by performing the process using the previous image data in any frame (the process of step SB9). It is possible to record a moving image with a uniform image quality (stream recording) until shooting is completed without causing a deterioration in image quality.

  In the present embodiment, when the ring buffer becomes full during moving image shooting, the amount of data written to the recording medium 20 is used by using the image data of the previous frame instead of the image data of the current frame. (Step SB9), but the moving image shooting may be stopped at that time. Even in such a case, at the next moving image shooting, a moving image can be recorded (stream recording) with a uniform image quality (frame rate, image size, compression rate) until the shooting is completed. However, the recording process of the recording information 300 in step SB10 described above needs to be performed before the moving image shooting process is completed.

  In addition, when the ring buffer becomes full during moving image shooting and the frame rate and bit rate for the next moving image shooting are lowered, the ring buffer area 14c capacity and the amount of data written when the ring buffer is full are used. However, the frame rate and the bit rate may be decreased by a predetermined ratio regardless of the ratio. In that case, the recording of the written data amount described above is naturally unnecessary. However, according to the present embodiment, the reduction rate of the frame rate and the bit rate can be minimized, and a higher quality moving image can be recorded at the next moving image shooting.

  Also in the present embodiment, the recording medium 20 is made to function as the information storage means of the present invention, and the recording information 300 is recorded on the recording medium 20. However, instead of the recording medium 20, the camera body side (for example, a program memory) 19) may be recorded. In this case, it is necessary to store the recording information together with the identification information for specifying the recording medium 20 in association with each other, and to read and use the recording information corresponding to the recording medium 20 (identification information) to be used. .

  Further, in the present embodiment, when the data writing performance in the recording medium 20 is deteriorated more than a certain level, an operation for displaying a message prompting the initialization of the recording medium is not performed. However, it may be implemented as in the first embodiment. However, in this case, as in the first embodiment, the writing time of the image data is measured while the moving image is being recorded, and the average writing speed is stored as history information for each shooting. In addition, a process for determining whether or not the data writing performance in the recording medium 20 has deteriorated more than a certain level is required.

  In the present embodiment, the image data temporarily stored in the ring buffer area 14c before writing to the recording medium 20 is the image data after compression encoding, but the YUV data before compression is used. Alternatively, Bayer data may be stored in the ring buffer area 14c.

  In step SB3 described above, when there is not enough space in the ring buffer area 14c to store the next image data, it is determined that the ring buffer state is “full”. When the free space in the buffer area 14c is lower than a predetermined amount, it may be determined that the buffer memory is full. In other words, whether or not the buffer memory is full may be determined based on whether or not the writing position and reading position of the image data in the ring buffer area 14c have a predetermined relationship.

  In addition, the rate at which the frame rate and the bit rate that were set last time are not yet written to the recording medium 20 when the image data writing position and the reading position in the ring buffer area 14c have a predetermined relationship. In addition, the ratio may be set in accordance with the ratio between the total size of the image data remaining in the ring buffer area 14c and the total size of the image data that has been written to the recording medium 20.

  Further, in the first embodiment, when any of the imaging timings arrives and the writing process of the image data of the previous frame on the recording medium 20 is not completed, the moving image to be recorded in the next moving image shooting In the second embodiment, the value of the recording parameters (frame rate, image size, compression rate) to be used next time is lowered so that the image quality of the image is reduced. Is set to “full”, the value of the recording parameter to be used next time is lowered, but it may be as follows.

  For example, as recording information, recording parameters (frame rate, image size, compression rate) used in the next moving image shooting are recorded on the recording medium 20 or the like, and the recording parameters recorded in advance are recorded in the next moving image shooting. You may make it perform moving image photography using.

  In addition, simply as video recording information, when any imaging timing arrives during moving image shooting, the state where the writing process of the image data of the previous frame to the recording medium 20 has not been completed, or the ring buffer state is “full” ”Is recorded, and it is determined from the flag information whether or not the above situation has occurred, and if this occurs, the recording parameter (frame rate) to be used next time is recorded. , Image size, compression rate) may be reduced.

  In the above description, the case where the present invention is applied to a digital camera having a moving image shooting function has been described. However, the present invention is not limited to this, and the present invention has a configuration for recording a moving image at the time of recording. If present, the present invention can be applied to various electronic camera devices such as a digital video camera, a camera-equipped mobile phone, a camera-equipped PDA, and a camera-equipped personal computer. Even in that case, the above-described effects can be obtained.

  Furthermore, a moving image that is compressed and recorded in an arbitrary format may be a moving image input from a video input terminal or a broadcast image of an analog television broadcast, for example. In addition, a recording medium for recording a moving image is not limited to a semiconductor memory, and may be a hard disk or the like.

1 Camera body 2 Optical system 3 CCD
12 LCD
13 CPU
14 Built-in memory 14a Image data work area 14b General-purpose work area 14c Ring buffer area 17 Built-in speaker 18 Key input block 19 Program memory 20 Recording medium 200 Recording information 300 Recording information

Claims (9)

Moving image recording means for sequentially recording image data constituting the moving image on a recording medium while performing image processing at a predetermined frame period;
Determination means for determining whether or not a delay that hinders normal recording of moving images has occurred in the writing processing of image data after image processing on the recording medium by the moving image recording means;
When it is determined by the determining means that the delay has occurred, information storage means for storing information indicating that,
A moving image comprising: an image quality setting unit that sets an image quality of a moving image recorded in a next recording operation by the moving image recording unit based on the information stored in the information storage unit Recording device. The information storage means stores image quality information indicating image quality of moving images sequentially recorded on a recording medium by the moving image recording means when it is determined that a delay has occurred by the determining means;
The image quality setting means sets the image quality of the moving image recorded in the next recording operation by the moving image recording means to an image quality lower by a predetermined ratio than the image quality indicated by the image quality information stored in the information storage means. The moving image recording apparatus according to claim 1, wherein the moving image recording apparatus is set. The information storage means stores image quality information indicating an image quality of a moving image recorded in a next recording operation by the moving image recording means when it is determined that a delay has occurred by the determining means;
The image quality setting means sets an image quality of a moving image recorded in a next recording operation by the moving image recording means to an image quality indicated by image quality information stored in the information storage means. Item 4. The moving image recording apparatus according to Item 1. Measuring means for measuring a time required when image data after image processing is recorded on the recording medium by the moving image recording means;
The image quality setting means determines the image quality of the moving image recorded in the next recording operation by the moving image recording means by the measuring means during the recording of the moving image when the determination means determines that the delay has occurred. 3. The moving image recording apparatus according to claim 2, wherein the image quality is set to be reduced by a ratio corresponding to an excess ratio with respect to a time allowed for recording the image data after the image processing in the measured required time. . A buffer memory that temporarily stores image data after image processing for a plurality of frames to be recorded on the recording medium;
The determining means determines that the delay has occurred when a write position and a read position of image data in the buffer memory have a predetermined relationship;
The image quality setting means records the image quality of a moving image recorded in the next recording operation by the moving image recording means, which is recorded in the buffer memory when the determination means determines that the delay has occurred. 2. The moving image according to claim 1, wherein the image quality is set to a quality reduced by a ratio corresponding to a ratio between a total size of image data not recorded on the medium and a total size of image data recorded on the recording medium. Recording device. Measuring means for measuring a time required when image data after image processing is recorded on the recording medium by the moving image recording means;
The average writing speed of data to the recording medium from the total required time measured by the measuring means during the recording of moving images by the moving image recording means and the total size of all image data recorded on the recording medium Speed calculating means for calculating
Speed history storage means for storing, as history information, an average writing speed calculated by the calculation means each time a new moving image is recorded on the recording medium by the moving image recording means;
Based on the history information stored in the speed history storage means, an acquisition means for acquiring the degree of deterioration of the average writing speed in a predetermined period;
The moving image recording according to any one of claims 1, 2, 3, and 5, further comprising a notifying means for notifying that the degree of deterioration acquired by the acquiring means exceeds a predetermined degree of deterioration. apparatus. In a moving image recording method for sequentially recording image data constituting a moving image on a recording medium while performing image processing at a predetermined frame period,
A step of determining whether or not a delay that hinders normal recording of a moving image has occurred in a writing process of image data after image processing on the recording medium;
When it is determined that the delay has occurred, storing information indicating that effect;
And a step of setting the image quality of the moving image to be recorded prior to the next moving image recording operation based on the stored information. A computer having a moving image recording apparatus for sequentially recording image data constituting a moving image on a recording medium while performing image processing at a predetermined frame period;
Moving image recording means for sequentially recording image data constituting the moving image on a recording medium while performing image processing at a predetermined frame period;
Determination means for determining whether or not a delay that hinders normal recording of moving images has occurred in the writing processing of image data after image processing on the recording medium by the moving image recording means;
Control means for storing information indicating that in the information storage means when it is determined by the determination means that the delay has occurred;
A program for functioning as image quality setting means for setting the image quality of a moving image recorded in the next recording operation by the moving image recording means based on the information stored in the information storage means. In an electronic camera device having a moving image photographing function for sequentially recording image data constituting a moving image captured by an imaging unit on a detachable recording medium while compressing at a predetermined frame cycle.
Moving image recording means for sequentially recording image data constituting the moving image on a recording medium while performing image processing at a predetermined frame period;
Determination means for determining whether or not a delay that hinders normal recording of moving images has occurred in the writing processing of image data after image processing on the recording medium by the moving image recording means;
Control means for storing information indicating that in the information storage means when it is determined by the determination means that the delay has occurred;
An electronic camera comprising: an image quality setting unit that sets an image quality of a moving image recorded in a next recording operation by the moving image recording unit based on the information stored in the information storage unit apparatus.

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