Method and system for generating a dummy bidirectional predictive field picture

Method and system for generating pseudo two-way prediction field image Technical field

[0001] The configuration of the present invention generally relates to a video system, and specifically, to a video system that records or replays a digitally encoded video sequence.

Background technique

[0002] In today's consumer electronics market, digital television (DTV) and high-definition television (HDTV) are becoming increasingly popular. Many purchasers of such televisions also purchase digital video recorders such as digital video disc (DVD) recorders or players in order to watch previously recorded programs or record their favorite programs. It is worth mentioning that the combination of a DTV (or HDVD) and a digital video recorder or player can be the main part of a home theater entertainment system.

[0003] A digital video recorder or player usually includes a Moving Picture Experts Group (MPEG) decoder for decoding digitally encoded multimedia data stored on a disc played by the video recorder or player. If the digital video recorder or player is connected to a conventional (non-DTV or non-HDTV) television, the digitally encoded signal will be decoded by the MPEG decoder of the digital video recorder or player before being displayed on the conventional television. However, it is worth noting that many DTVs contain their own MPEG decoders. Therefore, if a digital video recorder or player is connected to the DTV, the video signal read from the disc is remotely decoded by the DTV decoder. This structure can be referred to as a remote decoder configuration.

[0004] However, using a remote DTV decoder to decode a digitally encoded signal has a serious disadvantage. That is, it is very difficult to perform trick mode in this configuration. The trick mode can be any video playback in which it is played at an abnormal speed or in a non-forward direction. Generally, a trick mode includes repeating many images in a video signal such as during slow motion or stop motion trick modes. Since the bandwidth between the digital video recorder or player and the DTV is limited, repetition of the image in the signal being fed to the DTV may cause the signal to exceed the maximum bit rate limit of the transmission channel. If the image is an intra (I) image or a prediction (P) image, then, since these images can be coded with a relatively large amount of bits, the above problems will be more obvious.

[0005] In addition, even the processing of jump images such as during a fast motion trick mode may cause the average bit rate of the video signal to exceed the bit rate. Specifically, the first picture of a group of pictures (GOP) to be jumped during the fast motion trick mode is usually a bidirectional prediction (8) picture. Since this B picture is skipped, the average coded data amount of the remaining pictures in the GOP or the average number of bits per picture increases. Exceeding the bit rate limit of the transmission channel will result in buffer overflow and loss of images during the display of the trick mode video signal.

[0006] In addition to the problem of bit rate, remote decoding of video signals has another disadvantage: if the repeated image contains a moving target, the repeated display of non-progressive images in this configuration may cause the display The swing effect that appears in. In order to explain this shortcoming, it is necessary to briefly explain the interlaced scanning.

[0007] Many televisions use interlaced scanning technology. In this format, the video signal is usually divided into a predetermined number of horizontal lines. During each field period, only half of these lines are scanned; usually, odd-numbered lines are scanned during the first field period, and even-numbered lines are scanned during the next field period. Each scan is called a field, and when combined, the two fields form a complete image or frame. For an NTSC system, 60 fields are displayed per second, resulting in a rate of 30 frames per second.

[0008] When a moving target moves on the screen in an interlaced TV, each field will only display the moving target

Part. This partial display is because one field only displays the interlaced horizontal lines of the entire image. For example, for a particular field η, only odd horizontal lines are scanned, and the part of the moving object to be displayed in the field η is the part scanned during the swing of the odd horizontal lines of the field η. The next field, field n+1, is created after 1/60 second and will display the even-numbered horizontal lines of the image. Thus, the portion of the moving object displayed in the field n+1 is the portion scanned during the even-numbered horizontal line wobble of the field n+1. Although each field is different in time, because of the speed at which the field is displayed, the human eye regards the continuous display of the field as smooth motion.

[0009] If a viewer activates a trick mode, the trick mode video signal may contain repeated images recorded in an interlaced scan format. For example, if the viewer activates a stop-motion trick mode on a particular image, the image can be repeatedly sent to the DTV containing the remote decoder, decoded and displayed. However, the display of the repeated image is performed based on the normal display of the non-progressive image, that is, the fields constituting the non-progressive image are alternately displayed.

[0010] As explained above, if a moving target appears in an image recorded in an interlaced scan format, then each field will display the moving target at a specific position. As a result, since these fields are alternately displayed during the freeze-motion trick mode, the moving target on the display will quickly move from one position in the display to another and back again; from the effect point of view, the moving target vibrates. This kind of vibration occurs because the interleaved fields are different in time, and the moving targets appear in different positions in each field.

[0011] This problem also exists in DTV that includes a deinterleaver. As is known in the prior art, a deinterleaver can construct a complete frame from an interlaced field. Therefore, a deinterleaver can construct a complete frame from a field that includes repeated non-progressive frames. However, these complete frames constructed based on interlaced fields will also be displayed in an alternating manner, which may produce vibrating quality images. In addition, this vibration effect does not only appear in the freeze-frame special effect mode, but may also exist in any other special effect mode in which non-progressive images are repeated. Therefore, it is hoped that the problem of bit rate and vibration quality can be eliminated without increasing the cost and complexity of the system.

Summary of the invention

[0012] The present invention relates to a method of generating pseudo bidirectional prediction field images. The method includes the steps of: setting at least a part of the first indicator of the pseudo bidirectional predictive field image to indicate that encoding of the remaining signal will not occur; and setting at least a part of the second indicator of the pseudo bidirectional predictive field image to indicate that the Predict the pseudo-bidirectionally predicted field image from at least one of the first field and the last field of a reference image, thereby controlling the vibration quality image. The step of setting the first indicator further includes setting at least a part of the first indicator of the pseudo bidirectional predictive field image to indicate that discrete cosine transform DCT encoding of the residual signal will not occur.

[0013] In addition, the pseudo bidirectional prediction field image may include a plurality of macroblocks and in which at least a part of the first indicator is contained in one macroblock header. Each macro block may contain at least one motion vector having horizontal and vertical motion components, and the step of setting the first indicator may include the step of setting at least a part of the first indicator to indicate that the horizontal and vertical motion components are zero.

[0014] In one configuration, the pseudo bidirectionally predicted field image may be a backward predicted field image, and at least a part of the first indicator may include motion_code[0][1][0] flag and motion_code[0] [1] [1] Mark. The step of setting at least a part of the first indicator may include the step of setting the motion_code[0][1][0] flag and the motion_code[0][1][1] flag to a value of 1. In addition, the pseudo bidirectional prediction field image may be a forward predicted field image and at least a part of the first indicator may include motion_code [0] [0] [0] flag and motion_code [0] [0] [1] flag. The step of setting at least a part of the macroblock title may include marking motion_code[0][0][0]

And motion_code[0][0][1] marks the step set to value 1.

[0015] On the other hand, the reference image may be an intra image or a predicted image. In addition, the reference image may be a non-progressive image, a progressive image, or a field image. On the other hand, the pseudo bidirectional prediction field image may be a backward predicted field image, and at least one field used as the basis for prediction of the pseudo bidirectional prediction field image may be the first field of the reference image.

[0016] The first field may be a top field, at least a part of the second indicator may be located in a macroblock header, and in the macroblock header, at least a part of the second indicator may include motion_vertical_field_select [0] [1] flag . The step of setting at least a part of the second indicator may include the step of setting the motion_vertical_field_select[0][1] flag to a value of 0. In another configuration, the first field may be a bottom field, and at least a part of the second indicator may be located in a macroblock header. In the macroblock header, at least a part of the second indicator may include motion_vertical_field_select[0 ] [1] Mark. The step of setting at least a part of the second indicator may include the step of setting the motion_vertical_field_select[0][1] flag to a value of 1.

[0017] In still another configuration, the pseudo bidirectional prediction field image may be a forward prediction field image, and at least one field on which the pseudo bidirectional prediction field image is predicted is the tail field of the reference image. The last field may be a top field, and at least a part of the second indicator may be located in a macroblock header. In the macroblock header, at least a part of the second indicator includes a motion_vertical_field_select[0][0] mark. The step of setting at least a part of the second indicator may include the step of setting the motion_vertical_field_select[0][0] flag to a value of 0.

[0018] In addition, the trailer field may be a bottom field, and at least a part of the second indicator may be located in a macroblock header. In the macroblock header, at least a part of the second indicator may include motion_vertical_field_select [0] [0] Mark. The step of setting at least a part of the second indicator may include the step of setting the motion_vertical_field_select[0][0] flag to a value of 1. The method may further include the step of skipping at least a part of the macroblock when at least one field of the pseudo bidirectional prediction field image and the reference image have the same parity.

[0019] The present invention also relates to a system for generating pseudo bidirectional prediction field images. The system includes a controller and a processor for reading data from the storage medium. The processor is programmed to set at least a part of the first indicator of the pseudo bidirectional predictive field image to indicate that encoding of the remaining signal will not occur, and to set at least a part of the second indicator of the pseudo bidirectional predictive field image to It indicates that the pseudo bidirectional prediction field image will be predicted from at least one of the first field and the last field of a reference image to control the vibration quality image. The system also includes appropriate software and circuits for performing the above-described methods.

[0020] Brief Description of the Drawings

[0021] FIG. 1 is a block diagram showing a system capable of generating a pseudo bidirectional predictive image configured according to the present invention.

[0022] FIG. 2 is a flowchart showing the operation of generating a pseudo bidirectional predictive image according to the configuration of the present invention.

[0023] Figure 3 shows some parts of a typical MPEG syntax.

[0024] FIG. 4A shows a part of a typical group containing non-progressive images.

[0025] FIG. 4B shows several approaches for predicting pseudo bidirectionally predicted field images based on non-progressive reference images.

Detailed ways

[0026] FIG. 1 shows in the form of a block diagram a system 100 configured to implement various advanced operating features according to the present invention. However, the present invention is not limited to the specific system shown in FIG. 1, because the present invention can be implemented using any other system that can receive a digitally encoded signal and transmit the signal to a display device. In addition, the system 100 is not limited to reading/writing data from/to any specific type of storage media, because the system 100 can use any data that can store data.

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The storage medium of word coded data.

[0027] The system 100 may include a controller 110 for reading/writing data from/to the storage medium 112. The system 100 may also have a preprocessing engine 114, a microprocessor 116, a memory 118, a transmission buffer 120, and a display device 122. The preprocessing engine 114 may contain appropriate software and circuits for locating and setting or adjusting one or more specific flags or parameters in the digitally encoded video signal to generate a pseudo B-field image. A control and data interface may also be provided to allow the microprocessor 116 to control the operation of the controller 110 and the preprocessing engine 114. Appropriate software or firmware for the microprocessor 116 to perform conventional operations may be provided in the memory. In addition, the microprocessor 116 may be provided with a plurality of program routines according to the configuration of the present invention.

[0028] It should be understood that all or part of the preprocessing engine 114 and the microprocessor 116 may be the processor 124 in the concept of the present invention. In addition, all or part of the controller 110, the preprocessing engine 114, the microprocessor 116, and the transmission buffer 120 may be the bitstream source 126 in the concept of the present invention.

[0029] In another configuration, the display device 122 includes its own decoder 123 for decoding all or part of any video signal read from the storage medium 112 and processed by the bitstream source 126. In this particular configuration, the decoder (not shown) in the bitstream source 126 generally does not decode the video signal read from the storage medium 112. This particular embodiment can be referred to as a remote decoder configuration. However, it should be noted that the present invention is not limited to this configuration, because the present invention can be implemented in any other suitable system.

[0030] During operation, the controller 110 may read a video signal containing a plurality of images from the storage medium 112. These images can be non-progressive, progressive, or field images. In one configuration, if the microprocessor 116 receives a trick mode command, then the microprocessor 116 will signal the pre-processing engine 114 to locate and set or adjust a number of predetermined flags and MPEG syntaxes such as these field images. The parameters generate pseudo B-field images that can be predicted from multiple images in the digitally encoded video signal. Then, the pseudo B-field image may be transferred to the transmission buffer 120 and transferred to the display device 122. The decoder 123 can decode pseudo B-field images, and the display device 122 can display them.

[0031] The above discussion is an example of how to generate a pseudo B-field image once the microprocessor 116 receives a trick mode command. This process is called "on the fly" to generate pseudo B-field images. However, on the other hand, the preprocessing engine 114 and the microprocessor 116 can generate a pseudo B-field image before the trick mode command is initiated. As an example, a pseudo B-field image can be generated, and the microprocessor 116 can instruct the preprocessing engine 114 to transfer one or more pseudo-B-field images to the memory 118. At the memory 118, the pseudo B-field image can be stored until a trick mode command is received, at which time the microprocessor 116 can insert the pseudo-B-field image into the video signal. The overall operation of the present invention will be discussed in more detail below.

[0032] Generate pseudo bidirectional prediction field image

[0033] Referring to FIG. 2, method 200 shows one approach that can be used to generate pseudo B-field images. In one embodiment, a remote decoder configuration can be utilized to implement the present invention. In order to realize the present invention, a remote decoder configuration can be any system that can realize the following conditions, that is, in this system, at least a part of the image in the video signal can be provided by the bitstream source that provides the image to the decoder. The external decoder is not controlled by the bitstream source to decode. As an example, the bitstream source may be an optical storage media player or recorder capable of reading multimedia data from an optical storage medium and transmitting the data to a digital TV containing its own decoder via a transmission channel. However, it should be understood that the present invention is not limited to this example or this remote decoder configuration, as any other suitable system or configuration can be used to implement the present invention.

[0034] Referring to FIG. 3, this figure shows a part of a typical MPEG syntax 300 of a digitally encoded image. According to the invention

The configuration of this grammar 300 can represent the grammar of the pseudo B-field image. Figure 3 will be discussed below in conjunction with Figure 2 in order to describe how to generate a pseudo B-field image. It should be noted that only these parts of the syntax 300 related to generating pseudo B-field images from non-progressive frames, especially pseudo B-field images that can reduce the quality of the vibration image, will be discussed here. However, it is obvious to those skilled in the art that parts of the syntax 300 that are not discussed here are already known by using traditional B-field images, and pseudo B-field images can be predicted based on progressive images and field images.

[0035] Referring to FIG. 2, in step 210, a process for generating a pseudo B-field image from a non-progressive image is started. In step 212, the picture_coding_type parameter (not shown) included in the picture header 310 (see FIG. 3) of the syntax 300 may be set to indicate that the pseudo B-field picture will be a B picture. The picture_coding_type parameter is preferably a 3-bit parameter, and its value can be set to "011". In step 214, the f_code parameter can be set. In Figure 3, the f_code parameter 312 which usually includes 4-bit parameters f_code [0] [0], f_code [0] [1], f_code [1] [0] and f_code [1] [1] is located in the image coding extension header 314 in.

[0036] The pseudo B-field image may be a unidirectional prediction image. One-way prediction images are predicted based on only one image, while traditional B-frame images are usually predicted based on two separate images. Generally, the one-way pseudo B-field image can be a forward-predicted pseudo-B-field image or a reverse-predicted pseudo-B-field image. If the pseudo B-field image is a forward-predicted pseudo-B-field image, the pseudo-B-field image can be predicted based on a reference image before the pseudo-B-field image (in display order). On the contrary, if the pseudo B-field image is a reverse-predicted pseudo B-field image, then the pseudo B-field image can be predicted based on a reference image after the pseudo B-field image (in the display order). Since they only make predictions based on one image, one-way prediction of pseudo B-field images can be applied to repeated or duplicate images.

[0037] If the pseudo B field picture is a backward predicted field picture, then f_code[0][0] and f_code[0][1] can be set to the value of "1111" to indicate that no positive To forecast. In addition, f_code[l][0] and f_code[l][l] may be set to reflect the motion vector range value of the backward prediction. On the contrary, if the pseudo B field picture is a forward predicted field picture, then f_code[l][0] and f_code[l][1] can be set to the value of "1111" to indicate that no reverse will occur Prediction, and f_code[0][0] and f_code[0][1] can be set to reflect the motion vector range value of forward prediction.

[0038] Referring back to the method 200, in step 216, the picture_structue parameter (picture_structue 3 in FIG. 3 can be set to a value of "01" or "10". Setting the picture_structue parameter 315 to a value of "01" can indicate pseudo The B field picture is a top field picture. Setting the parameter 315 to a value of "10" can indicate that the pseudo B field picture is a bottom field picture. For the present invention and according to MPEG syntax, set the picture_structue parameter 315 to which of these values is It does not matter. If the pseudo B-field image is predicted based on the field image of a non-progressive image, then this principle can also be applied. For example, if the pseudo B-field image will be predicted based on the top field of a non-progressive image, Then, the picture_structue parameter 315 can be set to any of the above-mentioned values, and the pseudo B-field image can be a top field image or a bottom field image.

[0039] Continuing with the method 200, the frame_pred_frame_dct flag (frame_pred_frame_det flag 316 in FIG. 3) may be set to a value of 0, as shown in step 218. When constructing a pseudo B-field image, setting the frame_pred_frame_dct flag 316 to a value of "0" enables a decoder that decodes the pseudo B-field image to use field-based prediction. In addition, as shown in step 220, the top_field_first flag (top_field_first flag 319 in FIG. 3) can be set to a value of "0" according to the MPEG syntax of a field image.

[0040] At step 222 of the method 200, the following flags can be set to a value of "0": Q_scale_type (Q_scale_type flag 320 in FIG. 3), Intra_vic_format (Intra_vic_format flag 322 in FIG. 3), and

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Alternate_scan (Alternate_scan marked 324 in Figure 3). Since encoding of prediction errors and residual signals will not occur, these flags can be set to "0" values. In addition, since the remaining signals will not be encoded, the Quantiser_scale_code parameter (Quantiser_scale_code parameter 326 in Figure 3) can be set to the value of 00101. Looking back at Figure 3, the Quantiser_scale_code parameter 326 can be located in the slice header 327 (for simplicity, only one slice header 327 is shown in the syntax 300).

[0041] Since the pseudo B-field image may include multiple macroblocks, the syntax 300 may include multiple macroblock headers 328, where each macroblock header 328 can be associated with a single macroblock (with the segment header Similarly, to simplify the drawing, only one macroblock header (328) is shown in the syntax 300. The first indicator may be positioned within the macroblock header 328. In one configuration, part of the first indicator may be the macroblock_type parameter 330. 2 and 3, in step 224 of the method 200, the macroblock_type parameter 330 may be set to indicate that the encoding of the remaining signal will not occur. As an example, in a traditional B-field image, discrete cosine transform (DCT) is usually used to encode the remaining signal. Thus, in one configuration, DCT encoding of the remaining signal of each pseudo B-field image will not occur. However, it should be understood that the present invention is not limited to this consideration, because any other appropriate parameter can be set to indicate that it will not happen that the residual signal is encoded by DCT or any other algorithm.

[0042] In one configuration, the macroblock_type parameter 330 may be set to a value of "010". This setting indicates that the following flags (not shown) can be set to 0: macroblack_quant; macroblock_pattern; macroblock_intra; spatial_temporal_weight_code_flag and permitted_spatial_temporal_weight_classeso. In addition, this setting can indicate that the macroblock_motion_backward flag (not shown) can be set as a pseudo B field image. The "1" value used when being backward predicted. In another example, the value of the macroblock_type parameter 330 can be set to 0010. In this example, the setting is the same as discussed above except that the macroblock_motion_forward flag (not shown) can be set to the value 1 instead of the macroblock_motion_backward flag.

[0043] The field_motion_type parameter (field_motion_type parameter 332 in FIG. 3) may be set as shown in step 226. This setting can indicate that the type of prediction is field-based prediction, motion_vector_count is 1, mv_format is field and dmv is 0. Continuing to refer to the method 200, in step 228, a second indicator such as the motion_vertical_field_select flag may be set.

[0044] For example, referring to FIG. 3, motion_vertical_field_select[0][1] flag 334 and motion_vertical_field_select[0][0] flag 336 can be set to indicate which field of the reference image will be used to predict the pseudo B-field image. The motion_vertical_field_select[0][1] flag 334 is associated with the pseudo B-field image for backward prediction, and the motion_vertical_field_select[0][0] flag 336 is associated with the pseudo B-field image for forward prediction. However, the second indicator is not limited to these flags, and any other appropriate flags or parameters can be used to execute the desired prediction scheme.

[0045] As known in the prior art, certain macroblocks of digitally encoded images can be skipped according to the field parity of a reference image and a field or field image predicted from the reference image field (non-progressive frame image). As an example, if a video signal containing non-progressive images is being played back, then each reference image and non-reference image can have a top field and a bottom field. More specifically, if the bottom field of the non-reference image is predicted based on the field of the reference image with the same parity, then, in this case, the field of the reference image can be a bottom field, then it can be skipped A large number of macroblocks composed of the bottom field of a non-reference image.

[0046] In fact, if the related fields have the same parity, then all macroblocks composed of a segment except the first

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All except the first and last macro block can be skipped. The net result is that non-reference pictures will contain less coding information than would normally be required to encode such a picture. This process is also applied to field images. It is obvious to those skilled in the art that the macroblock_escape and macroblock_address_increment parameters in the MPEG syntax (not shown) can be manipulated to perform this processing.

[0047] The above discussion about jumping macroblocks also applies to the present invention. That is, if the generated pseudo B-field image is predicted based on a reference image in which the parity of the pseudo B-field image matches the parity of the field of the reference image, then one or more macros including the pseudo B-field image Blocks can be skipped. If the pseudo B-field image is predicted based on a reference field image with the same parity, the same situation can be generated. Jumping multiple macroblocks of pseudo B-field images can produce pseudo B-field images that contain very little coding information, which can help reduce the increased bit rate of the video signal into which these images are inserted.

[0048] The pseudo B-field image can be predicted based on any appropriate reference image. The reference image may for example be a progressive image, a non-progressive image or even a field image. In addition, the reference image may be, for example, an intra image or a predicted image. If the reference image is a non-progressive image, the reference image may include at least the first field and the last field. The first field may be a field of the reference field that is displayed before any other fields that constitute a reference field. Conversely, the tail field may be a field of the last displayed reference image among the fields including the reference image.

[0049] In many cases, the reference image may include a top field and a bottom field, the first field may be the top field, and the last field may be the bottom field. FIG. 4A shows an example of such a configuration, and the figure shows a part of an image group 400 in the display order. Picture I? may be a reference picture capable of predicting pseudo B-field pictures (and any other suitable reference picture in GOP 400 may be used). Image 1₂It may include a top field and a bottom field, where the letter "t" is used to identify one field as the top field, and the letter "b" is used to identify one field as the bottom field.

[0050] In this example, since field 5 will be displayed in normal playback, image 1₂So, it can be the first game. Similarly, since the field beak is the tail field of the image [2] to be displayed, it can be the tail field. Of course, the present invention is not limited to this example, because any other suitable field of a reference picture can be the first field or the last field. For example, in some cases, the image beak may be the image to be displayed 1₂The first field and can be a first field, and the image can be the last field to be displayed and can be a last field.

[0051] Looking back at Figure 3, if the pseudo B-field image is a backward predicted field image and the first field of a reference image is a top field, then the value of motion_vertical_field_select [0] [1] flag 334 can be set It is "0" to indicate that the pseudo B-field picture will be predicted based on the top field of the reference picture. In addition, if the pseudo B-field image is a forward-predicted pseudo-B-field image and the trailing field of the reference image is a bottom field, then the value of the motion_vertical_field_select[O][0] flag can be set to "1" to Instruct a decoder to predict pseudo B-field pictures based on the bottom field of the reference picture.

[0052] FIG. 4B shows examples of these specific prediction schemes. Similar to Figure 4A, image 1₂Can have a top field port and a bottom field I_2bOf a reference image. According to the configuration of the present invention, image 1 can be₂The first field, in this case, is the field port to predict the pseudo B-field image B for backward prediction. #The letter "d" indicates that the B picture is a pseudo B image, the letter "f" indicates that the image is a field image, and the letter "b" designates the pseudo B field image as a pseudo B field image for backward prediction.

[0053] In another configuration, according to image 1₂The last field in this example happens to be the field port to predict the pseudo B-field image Bdff for forward prediction. Similar to the above, the letter "d" and the letter "f" immediately following the letter "d" respectively indicate that the image is a pseudo B-field image. The second letter "f" indicates that the pseudo B field picture is a forward predicted field picture. It should be understood that the present invention is not limited to these examples. As a pseudo B-field image, there is no need to consider that it is a forward predictive image.

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It is also a backward-predicted field picture, which can be predicted based on any other appropriate field in the reference picture. In addition, the reference image is not limited to an I image, and may also be a P image.

[0054] However, predicting the pseudo B-field image according to the above example can assist in the control of the vibration quality image. Since the pseudo B-field image and the field of the reference image can be displayed in a manner that limits the amount of vibration of the moving target, it is possible to control the vibration quality image. For example, if the pseudo B field picture is a backward predicted field picture, then limiting the prediction of the pseudo B field picture and any subsequent backward predicted pseudo B field picture to prediction based on the first field of the reference picture will ensure that only A single movement of the moving target position occurs. This principle is applicable no matter how many backward-predicted pseudo B-field pictures are inserted into the video signal.

[0055] That is, a moving target will appear at a single position in the first field of each back-predicted pseudo-B field image and the reference image, and only move to a different position when displaying the second field of the reference image once. This discussion also applies to the pseudo B-field image of the forward prediction based on the second field prediction of the reference image. If the forward predicted image is predicted based on the second field of the reference image and the backward predicted image is predicted based on the first field, then any combination of forward and backward predicted pseudo B field images can also be used. Minimize the movement of the moving target.

[0056] Continuing with step 228 of FIG. 2, another part of the first indicator includes several motion_code flags, and these motion_code flags can be set. For example, according to the configuration of the present invention, the pseudo B-field image may include at least one motion vector having horizontal and vertical components. As shown in Figure 3, the motion vector may include motion_code[0] [1] [0] or [0] [1] [1] mark 338 and motion_code [0] [0] [0] or [0] [0] [1] Mark 340. motion_code [0] [1] [0] or [0] [1] [1] The mark 338 is a mark related to the pseudo B-field image of backward prediction, and motion_code[0] [0][0] or mark 340 is a pseudo B-field image for forward prediction. In one configuration, the value of the motion vector can be set to "1", thereby indicating that the horizontal and vertical motion components of the motion vector will have a value of 0.

[0057] Setting the values of the horizontal and vertical motion components to "0" without encoding the remaining signal allows the pseudo B-field image to include very few bits, especially when compared with the conventional I, P, or B-field images that include I, P, or B field images. This is especially true when comparing B images. Therefore, these images can be sent to a remote decoder via a transmission line to reduce the average bit rate of the trick mode video signal. However, it should be noted that the pseudo B-field pictures predicted from a reference picture are not limited to systems where remote decoding takes place, because these field pictures can be used in any other suitable configuration. Referring back to FIG. 2, although not shown in the method 200, each step of setting the flag or parameter associated with the macroblock of the pseudo B-field image, that is, steps 224, 226, and 228, can repeat each of the pseudo B-field images. Non-jump macro block. Finally, the method 200 ends in step 230.

[0058] Although the present invention has been described with reference to the embodiments, it should be understood that the foregoing description is only for illustration and not for limiting the scope of the present invention as defined by the claims.