Camera apparatus with magnified playback features

An embodiment of a camera apparatus includes transferring a compressed playback streaming signal output from a recording medium to a map defined in a memory circuit, decoding the transferred playback streaming signal by a decoder, converting the decoded signal to a YUV signal in an image processing unit, transferring the converted signal to the map as a YUV signal, generating a magnified or reduced image from the YUV signal in the image processing unit, and storing the image on the map, overlaying a magnified or reduced image prepared on the map according to a magnified playback request, and outputting the overlaid image for seeking an output position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2005-104426, filed Mar. 31, 2005, the entire contents of which are incorporated herein by reference.

BACKGROUND

One embodiment of the invention relates to a camera apparatus which can display a magnified or reduced image during playback, and in particular, a desired part of a still or moving image taken by a camera apparatus such as an electronic camera.

2. Description of the Related Art

A camera apparatus can record still and moving images in a recording medium, such as a semiconductor memory (a memory card) and a hard disc unit.

A taken image is displayed (played back) in a liquid crystal display provided integrally with a camera apparatus, a display unit capable of displaying a video signal, that is, a display unit used in a personal computer, or an ordinary television set, by the user by operating the camera apparatus.

Nowadays, as a camera apparatus and a large-screen television (monitor) have become widespread, partially magnified playback of a recorded image is widely demanded by the user.

Japanese Patent Application Publication (KOKAI) No. 2004-48229 discloses a display control method that is used when displaying a magnified still image in a digital still camera.

However, the Publication 2004-48229 mentions only display of a magnified still image and operations for it, and does not mention magnification or reduction of a desired part of a moving image during playback.

DETAILED DESCRIPTION

Various embodiments according to the invention will be described hereinafter with reference to the accompanying drawings. In general, according to one embodiment of the invention, an embodiment of a camera apparatus includes transferring a compressed playback streaming signal output from a recording medium to a map defined in a memory circuit, decoding the transferred playback streaming signal by a decoder, converting the decoded signal to a YUV signal in an image processing unit, transferring the converted signal to the map as a YUV signal, generating a magnified or reduced image from the YUV signal in the image processing unit, and storing the image on the map, overlaying a magnified or reduced image prepared on the map according to a magnified playback request, and outputting the overlaid image for seeking an output position.

FIGS. 1A and 1Bshow schematic illustrations of an electronic camera apparatus capable of recording still and moving images and sound, to which an embodiment of the present invention is applicable.

FIG. 1Ashows an electronic camera apparatus (an image pickup unit)1viewed from the camera lens side. The electronic camera apparatus1has a camera lens11, a flash12, a shutter button13(for a still image), and a remote control receiver14. The camera apparatus1also has an adapter connector (a connection terminal)15used for connection with a personal computer and an external power supply (a charger).

FIG. 1Bshows the electronic camera apparatus1viewed from the opposite side of the camera lens11.

The electronic camera apparatus1has a liquid crystal monitor (LCD panel)22and a speaker23provided integrally with a frame21functioning also as a main power switch. The electronic camera apparatus1also has a main power switch24at a fixed position, which is turned off at the position where the frame21is closed (housed at a fixed position of the main body of the electronic camera).

The electronic camera apparatus1has a record button25capable of inputting instructions (commands) to start and stop recording a moving image, a jog (JOG) dial26capable of inputting instructions (control commands) to input operation modes and conditions and select decisions, a set (OK) button27capable of inputting an instruction (a control command) to determine (execute) the instruction selected (guided) by the jog dial26, a zoom bar28capable of inputting a control signal for zoom operation to change the angle of an image (the angle to take a picture of a subject) to be taken by the camera lens11, and a menu button29used to input a control command to display a menu screen.

FIG. 2shows an example of a control system of the electronic camera apparatus shown schematically inFIGS. 1A and 1B.

A subject image taken by the camera lens11is focused on an image forming plane of the image pickup element31, or a CCD sensor, for example, and converted to an analog signal (taken image data).

The analog signal (taken image data) from the CCD sensor31is converted to a digital signal in an analog/digital (A/D) converter101controlled by a CPU (main control circuit)111, and input to a camera signal processing circuit102.

The camera signal processing circuit102performs gamma correction, color signal separation or white balance adjustment for the taken image data converted to a digital signal by the A/D converter101.

The taken image data output from the camera signal processing circuit102, or a recording image taken by the camera lens11, is input to a liquid crystal panel driver (LCD Driver)108, and displayed in an LCD panel22(hereinafter called LCD) mounted in the frame21(refer toFIG. 1B).

The taken image data output from the camera signal processing circuit102is compressed in a compression/expansion unit103, when recording, and recorded in a main recording medium, for example, a hard disc unit105(hereinafter abbreviated as HDD) or an attached removable recording medium, for example, a memory card106, or a nonvolatile memory.

The compression/expansion unit103compresses a still image by a known method such as JPEG, and a moving image (a non-still image) by MPEG. The memory card106may use a semiconductor memory called SD card (registered trademark) and Mini-SD (registered trademark).

When playing an image recorded in the HDD105or memory card106, an image read from the HDD105or memory card106is expanded in the compression/expansion unit103, and supplied to a video decoder107through a memory circuit104. The image data supplied to the video decoder107is displayed in the LCD22through the liquid crystal panel driver108.

A not-shown recording media interface is used for the transfer of data (compressed image) with the HDD105and memory card106. A video interface (Video I/F) and OSD (On Screen Display) processor121are provided in the stage preceding the video decoder107.

The video interface and OSD processor121is used to display a display frame or a sub-screen as explained later with reference toFIG. 3, when a magnified image of a desired part of an image displayed in the LCD22is displayed in a display frame or a sub-screen. An image overlaid through the OSD121is magnified or reduced by an image (magnification/reduction) processor131.

Naturally, a not-shown work memory (called RAM or cache) is provided for processing image data, as firmware of the CPU111, or as a part of the memory circuit104, or as an external memory connected to the memory circuit104.

Still image or moving image data recorded in the HDD105or memory card106can be transferred to a not-shown external unit, such as a personal computer (PC) and a video recorder. An interface controller109can be used for the transfer with an external unit. Naturally, a known standard, for example IEEE 1394, a parallel bus, a USB (Universal Serial Bus) can be used as an interface.

The interface controller109is inserted between an optional interface and the memory circuit104. Naturally, a network (LAN) connected through a LAN controller110can be used for the transfer of data.

In the HDD105as a recording medium, according to the capacity, the recordable number of still images or the time to record moving images (the number of titles) reaches several100to several1000. Thus, a high speed is demanded to feed the recorded images or titles forward and backward.

Therefore, the jog dial26and OK button27permit easy selection of many images or titles and setting of operation modes without hassle. (An easy-to-use switch such as the jog dial26is useful when specifying an image by continuously searching many images or titles.) The contents input by the jog dial26(by the user's operation), operation states of the camera apparatus1, or display of the menu screen by the menu button29are combined through the CPU111, memory circuit104, image (magnification/reduction) processor131, video interface and OSD121, and displayed in the LCD22.

The OK (set) button27gives the CPU111information that the button27is pressed (ON/OFF signal is input). Based on the ON/OFF signal input from the information (the button27), the CPU111determines the image/title or mode selected by the jog dial26, and plays the image/title or sets the mode.

The jog dial26sends the CPU (main control unit)111information about the rotation angle and speed. The CPU111controls the (next) image display speed based on this information.

The OK (set) button27is placed coaxially (concentrically) with the center of rotation of the jog dial26. The OK (set) button27can input the above-mentioned ON signal when pressed substantially toward the center (in the axial direction), and can input a control command (instruction) to scroll an image displayed in the LCD22in the pressed direction, when pressed in one of four directions (generally called “up/down/left/right”) dividing the circumference equally into four parts.

Displaying a magnified image of a specified part during playback of a still image has already been realized in most digital still cameras.

Further, as the part (position) of a whole image that is magnified becomes unclear when an image is magnified, a sub-screen or frame22-302is simultaneously displayed on the display screen22-301of the LCD22, and a magnified position mark or frame22-303is displayed to indicate the magnified area.

However, when displaying a magnified image while playing a moving image, special playback techniques such as frame-advance or time-lapse (extract a display image at every certain time) from a paused state is requested in many cases. Namely, if a part of a display screen is magnified when playing a moving image, seamless playback becomes difficult.

This proposal enables magnified display and scroll of a moving image without losing the real-time property, that is, overlaying identifying information indicating a magnification changing part of an image on a moving image displayed in a display unit, providing a magnified image corresponding to the magnification changing part of the moving image displayed in the display unit, and changing the magnified image corresponding to the magnification changing part according to a relative position instructed to change when an instruction is given to change a magnification changing part displayed on the moving image displayed in the display unit and a relative position of the moving image displayed in the display unit.

For example, as shown inFIG. 3A, when the zoom bar28of the camera apparatus1is moved to the T (Tele-conversion) side or W (Wide-angle) side during playback of an image with the whole image22-300of a playing image (moving image) being displayed in the LCD22, the image displayed in the LCD22is changed to the whole image22-301of a magnified part. In the whole image22-301of the magnified part, a reduced whole image is simultaneously displayed within a sub-screen or frame22-302. On the displayed reduced whole image22-302, a magnify position mark or frame22-303indicating a magnifying area is overlaid.

When the user instructs (inputs) to move a magnifying area to one of the “up/down/left/right” directions by operating the OK button27while the magnified image is being displayed, the magnify position mark22-303is moved within the displayed reduced whole image22-302.

Relating to the input of the instruction to move the magnify position mark22-303, the image displayed in the magnified whole image22-301is scrolled.

The reduced whole image22-303and magnify position mark22-303are erased (returned to the not-overlaid state) simultaneously with the reset of the magnified display mode, when a certain time (e.g., 3 to 5 seconds) passes after the stop of the operation of the zoom bar28or OK button27.

The above-mentioned partially magnified display during playback of a moving image is executed also in the state that playback of a moving image is temporarily stopped (paused). This improves the operability when specifying a magnifying image, or a magnifying object.

Further, when the zoom bar28is moved to the T side while a magnified image is being displayed (or subsequent to the operation of the zoom bar28during playback of an image), magnification (magnifying power) is increased. When the zoom bar28is moved to the W side, magnification is decreased. When magnification is increased to higher than a predetermined magnification (when the zoom bar28is moved to the T side), a magnifying image is temporarily created from an image with a maximum magnification or an image with a predetermined magnification among the transferable images, by pixel interpolation in an image (magnification/reduction) processing circuit explained below with reference toFIG. 4.

FIG. 4shows the configuration and signal flow to enable magnified display of a desired part of an image during playback of a moving image shown inFIGS. 3A and 3B. The components already explained inFIG. 2are given the same numerals, and a detailed explanation will be omitted. The same components as those inFIGS. 1A and 1Bare given the same numerals. Here, a continuous image consisting of an optional number of images taken within predetermined time is expressed as a moving image.

First, in label [A], an MPEG compressed playback streaming signal output from the HDD105(or the memory card106) is transferred to a map401of the SDRAM (memory circuit)104.

Then, in label [B] and label [C], the data is decoded in the compression/expansion unit (MPEG codec)103, and converted to a YUV signal for video display, and transferred to a map402of the SDRAM104, as a YUV signal.

The YUV signal, when displayed without modifying, is given OSD (here, the data corresponding to the frame of the sub-screen22-302on the display22-301and the frame of the magnify position mark22-303inFIG. 3A) in the video interface (Video I/F) and OSD (On Screen Display) processor121, converted to a video signal by the video decoder107, and displayed in the LCD22through the liquid crystal panel driver108. When displaying in an externally connected display unit, a signal output to a video output (Video Out) terminal can be used.

To create YUV data used for the magnified display, a YUV signal is input to the image (magnification/reduction) processor131(label [D]).

The image (magnification/reduction) processor131is an engine used to magnify or reduce an image (for full-screen display in a sub-screen), and high-speed processing is possible. In addition, existing techniques, such as bi-linear or bi-cubic interpolation and filtering may be used to increase the image quality. Most of these techniques have conventionally been used for magnification and reduction of a still image.

The image magnified or reduced in the image (magnification/reduction) processor131is stored in maps403(label [E]) and404(label [F]) of the SDRAM (memory circuit)104.

Namely, in the method of magnifying or reducing an image whenever requested for magnified or reduced display of a playback image in the present invention, an image used for magnified or reduced display is previously prepared and sequentially transferred (output) according to a transfer request. This is simple and low cost. With the recent high-speed (decreased processing speed) hardware structure (SDRAM), an image can be processed in real time if the size is standard. An image (a moving image or continuous images) displayed in the LCD22through the OSD processor121, or the data corresponding to the frame of the sub-screen22-302in the display22-301and the frame of the magnify position mark22-303inFIG. 3Ais sequentially moved when movement in the direction of “up/down/left/right” is instructed (input) from the OK button27, an area of an original image to be magnified is changed according to the range of moving the frame of the magnify position mark22-303, and the corresponding magnified or reduced image is sequentially stored in the maps403(label [E]) and404(label [F]) of the SDRAM104.

Thereafter, the magnified or reduced image prepared in the maps403and404of the SDRAM (memory circuit)104in the above-mentioned process is output to the video decoder107(label [G]) through the video interface and OSD processor21, with the magnified display screen and sub-screen overlaid on the OSD of a square area calculated by the CPU111.

Therefore, the LCD22displays the sub-screen22-302and the OSD image22-303overlaid on the sub-screen22-302, on the already magnified image22-301shown inFIG. 3A. In this time, the identifying information (22-303) indicating a magnification changing part is overlaid on a moving image displayed in the display unit (LCD22), and a magnified image corresponding to the magnification changing part (the image within the frame22-303) to be displayed in the moving image displayed in the display unit (a plurality of image is stored in the above-mentioned map). When an instruction to change the magnification changing part displayed in the moving image displayed in the display unit and the relative position of the moving image displayed in the display unit is input through the OK button27, the magnified image corresponding to the magnification changing part is changed according to the relative position instructed to change.

The sub-screen22-302can be made translucent, for example (the luminance and color are controlled so that the image is displayed in a transparent state through the magnified image22-301, and displayed in being overlaid), by controlling the output level from the image (magnification/reduction) processor131.

The above-mentioned magnified and reduced images utilize the high-speed image data transfer with the SDRAM (memory circuit)104, and can be easily realized by the above-mentioned simple method.

Playback such as reverse playback, fast forward playback, step playback and slow playback are the processes before the data is stored in the YUV map for video display in the image (magnification/reduction) processor131of the present invention, and can be scrolled while maintaining the state of magnified display.

Therefore, magnified display is possible while playing a moving image, and this playback image can be enjoyed. Further, a sub-screen also displays a moving image, and the whole image can be grasped even when magnifying the image. The method is simple, and the cost is not increased.

The embodiment of invention is also applicable to a video camera using a tape as a recording medium, for example, without modifications. A camera may be a still camera for shooting (recording) a still image, using a large capacity memory card as a main recording medium, and an optional external recording medium as an auxiliary recording medium.