WO2017063168A1 - Image coding method and apparatus, and image processing device - Google Patents

Abstract

An image coding method and apparatus, and an image processing device. The image coding method comprises: determining information about the number of color components and information about the number of bits used by the color components; and not coding the information about the number of bits used by each color component to a PPS corresponding to an image frame when parameters of the image frame are coded. Thus, redundant information can be reduced, bit costs for coding are further reduced, and a grammatical structure of an HEVC can be optimized.

Description

Image coding method, device and image processing device Technical field

The present invention relates to the field of graphic image technology, and in particular, to an image encoding method, apparatus, and image processing apparatus.

Background technique

In the current High Efficiency Video Coding (HEVC) standard JCTVC-U1005, one stream or multiple streams (also called sequences) can be image-encoded, and each stream can have a sequence parameter set (SPS). , Sequence Parameter Set), for example, SPS can be placed in the header area of the stream. Each stream may correspond to one or more image frames, each image frame having a Picture Parameter Set (PPS), for example, the PPS may be placed in the header file area of the image frame.

Image coding can use a Palette Predictor. The number information of the color component when the palette is predicted (ie, how many color components are there, for example, only the luminance component when the color is monochromatic, the color component has only one; when the plurality of colors can include the luminance component and the chrominance component, the color The components are, for example, three) can be defined in the chroma_format_idc of the SPS, and the bit number information used by the color component (which can be called bit-depth, for example, each bit of the color component is represented by several bits) can be defined in the seq_parameter_set_rbsp() of the SPS. .

In addition, the number information of the color component may also be defined in pps_scc_extension() of the PPS, for example, defined as monochrome_palette_flag; and the bit number information used by the color component may also be defined in the pps_scc_extension() of the PPS, for example, defined as luma_bit_depth_entry_minus8 And chroma_bit_depth_entry_minus8.

It should be noted that the above description of the technical background is only for the purpose of facilitating a clear and complete description of the technical solutions of the present invention, and is convenient for understanding by those skilled in the art. The above technical solutions are not considered to be well known to those skilled in the art simply because these aspects are set forth in the background section of the present invention.

Summary of the invention

However, the inventors have found that for the case where one SPS corresponds to a plurality of PPSs, both the SPS and the PPS contain the number information of the color components and the bit number information used for the color components, that is, the color components, due to the consistency requirement of the bit stream. The number information and the number of bits used by the color components appear redundant during encoding and decoding. I.

Embodiments of the present invention provide an image encoding method, apparatus, and image processing apparatus. The purpose is to reduce the number of pieces of color components and the redundancy of the bit number information used by the color components, thereby reducing the bit cost of encoding and optimizing the syntax structure of HEVC.

According to a first aspect of the embodiments of the present invention, an image encoding method is provided, including:

Determining the number information of the color component and the number of bits used by the color component;

The bit number information used by the color component is not encoded to the picture parameter set corresponding to the image frame when encoding the parameters of the image frame.

According to a second aspect of the embodiments of the present invention, an image encoding apparatus is provided, including:

An information determining unit that determines the number information of the color component and the bit number information used by the color component;

And a coding unit that does not encode the bit number information used by the color component to a picture parameter set corresponding to the image frame when encoding the parameters of the image frame.

According to a third aspect of the embodiments of the present invention, an image processing apparatus is provided, including:

An image encoder that determines number information of a color component and bit number information used by the color component; and does not encode bit number information used by the color component to the image frame when encoding parameters of the image frame Corresponding picture parameter set; and/or

And an image decoder that determines bit number information used by the color component according to a sequence parameter set corresponding to the stream in which the image frame is located, and decodes the image frame.

According to still another aspect of an embodiment of the present invention, a computer readable program is provided, wherein when the program is executed in an image processing apparatus, the program causes a computer to perform image encoding as described above in the image processing apparatus Method and/or corresponding image decoding method.

According to still another aspect of an embodiment of the present invention, a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform an image encoding method as described above and/or a corresponding one in an image processing device Image decoding method.

An advantageous effect of the embodiment of the present invention is that the bit number information used by the color component is not encoded into the PPS corresponding to the image frame when encoding the image frame. This not only reduces redundant information, further reduces the bit cost of encoding, but also optimizes the syntax structure of HEVC.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and the drawings, in which <RTIgt; It should be understood that the embodiments of the invention are not limited in scope. In The embodiments of the present invention include many variations, modifications, and equivalents within the scope of the spirit and scope of the appended claims.

Features described and/or illustrated with respect to one embodiment may be used in one or more other embodiments in the same or similar manner, in combination with, or in place of, features in other embodiments. .

It should be emphasized that the term "comprising" or "comprises" or "comprising" or "comprising" or "comprising" or "comprising" or "comprises"

DRAWINGS

Many aspects of the invention can be better understood with reference to the following drawings. The components in the figures are not drawn to scale, but only to illustrate the principles of the invention. In order to facilitate the illustration and description of some parts of the invention, the corresponding parts in the figures may be enlarged or reduced.

Elements and features described in one of the figures or one embodiment of the invention may be combined with elements and features illustrated in one or more other figures or embodiments. In the accompanying drawings, like reference numerals refer to the

1 is a schematic diagram of an image encoding method according to Embodiment 1 of the present invention;

2 is another schematic diagram of an image encoding method according to Embodiment 1 of the present invention;

3 is another schematic diagram of an image encoding method according to Embodiment 1 of the present invention;

4 is a schematic diagram of an image coding apparatus according to Embodiment 2 of the present invention;

Figure 5 is a block diagram showing the structure of an image encoder according to a second embodiment of the present invention;

Figure 6 is a diagram showing an image processing apparatus according to a third embodiment of the present invention.

detailed description

The foregoing and other features of the present invention will be apparent from the The specific embodiments of the present invention are disclosed in the specification and the drawings, which are illustrated in the embodiment of the invention The invention includes all modifications, variations and equivalents falling within the scope of the appended claims.

In JCTVC-U1005, the palette initialization portion in the SPS of Screen Content Coding (SCC) defines the number information of the color component and the bit number information used by the color component.

Table 1 shows a part of the syntax of the SPS.

Table 1

As shown in Table 1, the number information of the color component initialized by the palette prediction can be obtained from the chroma_format_idc in the SPS. Further, the bit number information used for the color component is obtained by adding a bit syntax element obtained by decoding in the SPS by 8, such as the syntax elements bit_depth_luma_minus8 and bit_depth_chroma_minus8 in Table 2 below.

Table 2 shows another part of the syntax of the SPS.

Table 2

In JCTVC-U1005, the palette initialization portion of the PPS of the SCC also defines the number information of the color components and the number of bits used for the color components.

Table 3 shows a part of the syntax of the PPS.

table 3

As shown in Table 3, the number information of the color component initialized by the palette prediction can be obtained from the monochrome_palette_flag in the PPS. Further, the bit number information used for the color component can be obtained from luma_bit_depth_entry_minus8 and chroma_bit_depth_entry_minus8 in the PPS.

Due to the consistency requirement of bitstream encoding, when the monochrome_palette_flag in the PPS is equal to 1, the chroma_format_idc in the SPS should be 0; when the monochrome_palette_flag in the PPS is equal to 0, the chroma_format_idc in the SPS should be a value greater than 0 (for example, 1, 2) Or 3).

In addition, the bit-depth related information BitDepthEntryY (where BitDepthEntryY=8+luma_bit_depth_entry_minus8) of the luminance component in the PPS should be equal to the bit-depth related information BitDepthY of the luminance component in the SPS; the bit-depth correlation of the chroma component in the PPS Information BitDepthEntryC (where BitDepthEntryC=8+chroma_bit_depth_entry_minus8) should be equal to the bit-depth related information BitDepthC of the luminance component in the SPS.

Therefore, the number information of the color component and the bit number information used for the color component are encoded not only in the SPS portion but also in the PPS portion. For example, monochrome_palette_flag, luma_bit_depth_entry_minus8, chroma_bit_depth_entry_minus8 in the PPS can be obtained from related information in the SPS. The current coding method not only leads to redundant information, but also the grammatical structure is not clear enough.

The embodiments of the present invention are described in detail below.

Example 1

Embodiments of the present invention provide an image encoding method. FIG. 1 is a schematic diagram of an image encoding method according to an embodiment of the present invention. As shown in FIG. 1, the image encoding method includes:

Step 101, determining number information of a color component and bit number information used by the color component;

Step 102: When encoding the parameters of the image frame, the bit number information used by the color component is not encoded into the PPS corresponding to the image frame.

In this embodiment, the video image may be encoded into one or more streams, each stream having an SPS and may contain one or more image frames; each image frame having a PPS. Further, the number information of the color component and the bit number information used for the color component may be predetermined before encoding the image frame, and any existing method may be employed.

When encoding an image frame, the SPS of the stream corresponding to the image frame may have been encoded; in this case, the bit number information used by the color component may not be encoded into the PPS corresponding to the image frame. In the middle, according to SPS can get this information.

2 is another schematic diagram of an image encoding method according to an embodiment of the present invention, showing an embodiment of the present invention. As shown in FIG. 2, the image encoding method includes:

Step 201: Determine the number information of the color component and the bit number information used by the color component when encoding the parameter of the stream;

In the present embodiment, bit_depth_luma_minus8 and bit_depth_chroma_minus8 in the chroma_format_idc and seq_parameter_set_rbsp() of the SPS may be determined; specifically, as described in the existing standard.

Step 202: Encode the number information of the color component and the number of bits used by the color component into the SPS corresponding to the stream when encoding the parameter of the stream;

In this embodiment, the bit_depth_luma_minus8 and the bit_depth_chroma_minus8 in the chroma_format_idc and seq_parameter_set_rbsp() of the SPS may be bit-stream encoded; as described in the existing standard.

Step 203: Determine, when encoding the parameters of the image frame, the number information of the color component and the bit number information used by the color component;

In this embodiment, the monochrome_palette_flag, luma_bit_depth_entry_minus8, chroma_bit_depth_entry_minus8 of the PPS may be determined; specifically, as described in the existing standard.

Step 204: When encoding the parameters of the image frame, encode the number information of the color component to the PPS corresponding to the image frame, and not encode the bit number information used by the color component to the PPS corresponding to the image frame.

In the present embodiment, the encoding of the SPS parameters may remain unchanged, and the encoding of the PPS parameters may delete the bit number information used by the color components.

Table 4 schematically shows a part of the syntax of the PPS of the present embodiment. For example, the bit-depth related information is deleted in the PPS.

Table 4

Assume that one SPS corresponds to N PPS. If the existing standard is adopted, it is assumed that SPS requires SPS_org bits in encoding, and N PPS requires PPS_org1, PPS_org2, ... PPS_orgN bits respectively; the bit-depth of luminance component and chrominance component is 8bit.

Taking the shortest bit sequence as an example, SPS and PPS require the following number of bits to encode:

Total_org=SPS_org+PPS_org1+PPS_org2+...+PPS_orgN.

After adopting the coding method shown in Table 4, SPS and PPS require the following number of bits to encode:

Total_new=SPS_org+PPS_org1-2+PPS_org2-2+...+PPS_orgN-2=Total_org–2*N.

Thus, the embodiment of the present invention can not only reduce redundant information, further reduce the bit cost of encoding, but also optimize the syntax structure of HEVC.

It is to be noted that FIG. 2 only schematically shows the case of the present embodiment, but the present invention is not limited thereto. For example, step 201 and step 203 may be combined, or step 203 may be omitted. The order of execution of each step may be changed according to actual conditions, or other steps may be added, or one or more of the steps may be omitted or merged. In addition, regarding the specific content of how to perform bit stream encoding, etc., reference may be made to related art.

In other embodiments, the number information of the color components may not be encoded into the PPS corresponding to the image frame in step 203; that is, the monochrome_palette_flag in Table 4 may also be deleted.

3 is another schematic diagram of an image encoding method according to an embodiment of the present invention, showing another embodiment of the present invention. As shown in FIG. 3, the image encoding method includes:

Step 301: Determine the number information of the color component and the bit number information used by the color component when encoding the parameter of the stream;

In the present embodiment, bit_depth_luma_minus8 and bit_depth_chroma_minus8 in the chroma_format_idc and seq_parameter_set_rbsp() of the SPS may be determined; specifically, as described in the existing standard. In addition, it is also possible to determine monochrome_palette_flag, luma_bit_depth_entry_minus8, chroma_bit_depth_entry_minus8 when encoding the parameters of the stream.

Step 302, when encoding the parameter of the stream, encoding the number information of the color component and the number of bits used by the color component into the SPS corresponding to the stream;

In this embodiment, the bit_depth_luma_minus8 and the bit_depth_chroma_minus8 in the chroma_format_idc and seq_parameter_set_rbsp() of the SPS may be bit-stream encoded; specifically, as described in the existing standard. In addition, monochrome_palette_flag, luma_bit_depth_entry_minus8, chroma_bit_depth_entry_minus8 can also be encoded into the SPS.

Table 5 schematically shows a part of the syntax of the SPS of the present embodiment. For example, the number information of the color component and the information about the bit-depth are added to the SPS.

table 5

Step 303: When encoding the parameters of the image frame, the number information of the color component is not encoded into the PPS corresponding to the image frame, and the bit number information used by the color component is not encoded into the PPS corresponding to the image frame.

Table 6 schematically shows a part of the syntax of the PPS of the present embodiment. For example, the number information of the color component and the related information of the bit-depth are deleted in the PPS.

Table 6

Assume that one SPS corresponds to N PPS. If the existing standard is adopted, it is assumed that SPS requires SPS_org bits in encoding, and N PPS requires PPS_org1, PPS_org2, ... PPS_orgN bits respectively; the bit-depth of luminance component and chrominance component is 8bit.

Taking the shortest bit sequence as an example, SPS and PPS require the following number of bits to encode:

Total_org=SPS_org+PPS_org1+PPS_org2+...+PPS_orgN.

After adopting the coding methods as shown in Table 5 and Table 6, SPS and PPS require the following number of bits to encode:

Total_new=SPS_org+3+PPS_org1-3+PPS_org2-3+...+PPS_orgN-3=Total_org+3-3*N.

Thus, the embodiment of the present invention can not only reduce redundant information, further reduce the bit cost of encoding, but also optimize the syntax structure of HEVC.

It is to be noted that FIG. 3 only schematically shows the case of the present embodiment, but the present invention is not limited thereto. The order of execution of each step may be changed according to actual conditions, or other steps may be added, or one or more of the steps may be omitted or merged. In addition, regarding the specific content of how to perform bit stream encoding, etc., reference may be made to related art.

It can be seen from the foregoing embodiment that the bit number information used by the color component may not be encoded into the PPS corresponding to the image frame when encoding the image frame; further, the number information of the color component may not be encoded into the image frame. Corresponding to the PPS. This not only reduces redundant information, further reduces the bit cost of encoding, but also optimizes the syntax structure of HEVC.

Example 2

An embodiment of the present invention provides an image encoding apparatus, which corresponds to the image encoding method in Embodiment 1, and the same content is not described herein again.

4 is a schematic diagram of an image encoding apparatus according to an embodiment of the present invention. As shown in FIG. 4, the image encoding apparatus 400 includes:

The information determining unit 401 determines the number information of the color component and the bit number information used by the color component;

The encoding unit 402 does not encode the bit number information used by the color component to the PPS corresponding to the image frame when encoding the parameters of the image frame.

It is to be noted that FIG. 4 only schematically shows a part of the image encoding apparatus related to the embodiment of the present invention. Unit, but the invention is not limited thereto. For other units of image coding (for example, a unit for determining a color palette, etc.), reference may be made to the prior art, and details are not described herein again.

In an embodiment, the encoding unit 402 is further configured to: not encode the number information of the color component to the PPS corresponding to the image frame.

In another embodiment, the encoding unit 402 is further configured to: when the parameter of the stream in which the image frame is located, encode the number information of the color component and the bit number information used by the color component to the stream Corresponding SPS.

In another embodiment, the encoding unit 402 is further configured to: encode the number information of the color component to the PPS corresponding to the image frame.

In this embodiment, the number information of the color component may be represented as monochrome_palette_flag;

In the case where the color component is a luminance component, the bit number information used by the color component may be expressed as luma_bit_depth_entry_minus8; in the case where the color component includes a luminance component and a chrominance component, the bit number information used by the color component may be expressed as luma_bit_depth_entry_minus8 and Chroma_bit_depth_entry_minus8.

An embodiment of the present invention also provides an image encoder comprising the image encoding device 400 as described above.

FIG. 5 is a schematic diagram showing the structure of an image encoder according to an embodiment of the present invention. As shown in FIG. 5, image encoder 500 can include a central processing unit (CPU) 100 and memory 110; memory 110 is coupled to central processor 100. The memory 110 can store various data; in addition, a program for information processing is stored, and the program is executed under the control of the central processing unit 100.

In one embodiment, the functionality of image encoding device 400 may be integrated into central processor 100. Wherein, the central processing unit 100 can be configured to implement the image encoding method as described in Embodiment 1.

In another embodiment, the image encoding device 400 can be configured separately from the central processing unit. For example, the image encoding device 400 can be configured as a chip connected to the central processing unit 100, and the image encoding device 400 can be implemented by control of the central processing unit. Features.

In addition, as shown in FIG. 5, the image encoder 500 may further include: an input and output unit 120, a display unit 130, and the like; wherein the functions of the above components are similar to those of the prior art, and details are not described herein again. It should be noted that the image encoder 500 does not necessarily have to include all of the components shown in FIG. 5; in addition, the image encoder 500 may also include components not shown in FIG. 5, and reference may be made to the prior art.

It can be seen from the above embodiment that the number of bits used for the color component may not be used when encoding the image frame. The information is encoded into the PPS corresponding to the image frame; further, the number information of the color component may not be encoded into the PPS corresponding to the image frame. Thereby, not only the redundant information can be reduced, the bit cost of the encoding is further reduced, and the syntax structure of the HEVC can be optimized.

Example 3

An embodiment of the present invention provides an image processing apparatus, where the image processing apparatus includes the image encoder as described in Embodiment 2, and further includes a corresponding image decoder. The same content of the embodiment of the present invention and the first and second embodiments will not be described again.

FIG. 6 is a schematic diagram of an image processing apparatus according to an embodiment of the present invention. As shown in FIG. 6, the image processing apparatus 600 includes:

The image encoder 601 determines the number information of the color component and the bit number information used by the color component; and encodes the bit number information used by the color component to the image frame when encoding the parameter of the image frame Corresponding PPS; and/or

The image decoder 602 determines the bit number information used by the color component according to the SPS corresponding to the stream in which the image frame is located, and decodes the image frame.

In an embodiment, the image encoder 601 may not encode the number information of the color component to the PPS corresponding to the image frame; and the image decoder 602 may determine the color component according to the SPS corresponding to the stream in which the image frame is located. Number of information.

In another embodiment, the image encoder 601 may encode the number information of the color component and the bit number information used by the color component to the SPS corresponding to the stream when encoding the parameter of the stream in which the image frame is located. .

In another embodiment, the image encoder 601 may also encode the number information of the color components to the PPS corresponding to the image frame.

In this embodiment, the configuration of the image encoder 601 and/or the image decoder 602 can be referred to FIG. 5; that is, the architecture of the CPU plus Memory can be implemented. The image encoder 601 can implement the image encoding method described in Embodiment 1, and the image decoder 602 can implement the image decoding method corresponding to the image encoding method of Embodiment 1.

The embodiment of the present invention further provides a computer readable program, wherein when the program is executed in an image processing apparatus, the program causes a computer to execute the image encoding method as described in Embodiment 1 in the image processing apparatus and / or the corresponding image decoding method.

Embodiments of the present invention also provide a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform an image encoding method and/or corresponding image decoding as described in Embodiment 1 in an image processing apparatus method.

The above apparatus and method of the present invention may be implemented by hardware or by hardware in combination with software. The present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps. The present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, or the like.

One or more of the functional blocks described in the figures and/or one or more combinations of functional blocks may be implemented as a general purpose processor, digital signal processor (DSP) for performing the functions described herein. An application specific integrated circuit (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, or any suitable combination thereof. One or more of the functional blocks described with respect to the figures and/or one or more combinations of functional blocks may also be implemented as a combination of computing devices, eg, a combination of a DSP and a microprocessor, multiple microprocessors One or more microprocessors in conjunction with DSP communication or any other such configuration.

The present invention has been described in connection with the specific embodiments thereof, and it should be understood by those skilled in the art that A person skilled in the art can make various modifications and changes to the present invention within the scope of the present invention.

Claims (14)

An image encoding method, the image encoding method comprising: Determining the number information of the color component and the number of bits used by the color component; The bit number information used by the color component is not encoded to the picture parameter set corresponding to the image frame when encoding the parameters of the image frame. The image encoding method according to claim 1, wherein the method further comprises: The number information of the color component is not encoded into a picture parameter set corresponding to the image frame. The image encoding method according to claim 2, wherein the method further comprises: When encoding the parameters of the stream in which the image frame is located, the number information of the color component and the bit number information used by the color component are encoded into a sequence parameter set corresponding to the stream. The image encoding method according to claim 1, wherein the method further comprises: The number information of the color component is encoded into a picture parameter set corresponding to the image frame. The image encoding method according to claim 1, wherein the number information of the color component is represented as monochrome_palette_flag; In the case where the color component is a luminance component, the bit number information used by the color component is represented as luma_bit_depth_entry_minus8; in the case where the color component includes a luminance component and a chrominance component, bits used by the color component The number information is represented as luma_bit_depth_entry_minus8 and chroma_bit_depth_entry_minus8. An image encoding device, the image encoding device comprising: An information determining unit that determines the number information of the color component and the bit number information used by the color component; And a coding unit that does not encode the bit number information used by the color component to a picture parameter set corresponding to the image frame when encoding the parameters of the image frame. The image encoding apparatus according to claim 6, wherein the encoding unit is further configured to: not encode the number information of the color component to a picture parameter set corresponding to the image frame. The image encoding apparatus according to claim 7, wherein said encoding unit is further configured to: when encoding a parameter of a stream in which said image frame is located, number information of said color component and said color component The number of bits used is encoded into the sequence parameter set corresponding to the stream. The image encoding apparatus according to claim 6, wherein said encoding unit is further configured to: The number information of the color components is encoded into a picture parameter set corresponding to the image frame. The image encoding device according to claim 6, wherein the number information of the color component is represented as monochrome_palette_flag; In the case where the color component is a luminance component, the bit number information used by the color component is represented as luma_bit_depth_entry_minus8; in the case where the color component includes a luminance component and a chrominance component, bits used by the color component The number information is represented as luma_bit_depth_entry_minus8 and chroma_bit_depth_entry_minus8. An image processing apparatus, the image processing apparatus comprising: An image encoder that determines number information of a color component and bit number information used by a color component; and does not encode bit number information used by the color component to the image frame when encoding a parameter of the image frame Corresponding picture parameter set; and/or And an image decoder that determines bit number information used by the color component according to a sequence parameter set corresponding to the stream in which the image frame is located, and decodes the image frame. The image processing device according to claim 11, wherein the image encoder does not encode the number information of the color component to a picture parameter set corresponding to the image frame; The image decoder determines the number information of the color component according to a sequence parameter set corresponding to the stream in which the image frame is located. The image encoding apparatus according to claim 12, wherein said image encoder uses the number information of said color component and said color component when encoding a parameter of a stream in which said image frame is located The bit number information is encoded into a sequence parameter set corresponding to the stream. The image encoding apparatus according to claim 11, wherein said image encoder encodes the number information of said color components to a picture parameter set corresponding to said image frame.

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