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FFmpeg/libavcodec/vc2enc_dwt.h

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avcodec: add a native SMPTE VC-2 HQ encoder This commit adds a new encoder capable of creating BBC/SMPTE Dirac/VC-2 HQ profile files. Dirac is a wavelet based codec created by the BBC a little more than 10 years ago. Since then, wavelets have mostly gone out of style as they did not provide adequate encoding gains at lower bitrates. Dirac was a fully featured video codec equipped with perceptual masking, support for most popular pixel formats, interlacing, overlapped-block motion compensation, and other features. It found new life after being stripped of various features and standardized as the VC-2 codec by the SMPTE with an extra profile, the HQ profile that this encoder supports, added. The HQ profile was based off of the Low-Delay profile previously existing in Dirac. The profile forbids DC prediction and arithmetic coding to focus on high performance and low delay at higher bitrates. The standard bitrates for this profile vary but generally 1:4 compression is expected (~525 Mbps vs the 2200 Mbps for uncompressed 1080p50). The codec only supports I-frames, hence the high bitrates. The structure of this encoder is simple: do a DWT transform on the entire image, split it into multiple slices (specified by the user) and encode them in parallel. All of the slices are of the same size, making rate control and threading very trivial. Although only in C, this encoder is capable of 30 frames per second on an 4 core 8 threads Ivy Bridge. A lookup table is used to encode most of the coefficients. No code was used from the GSoC encoder from 2007 except for the 2 transform functions in diracenc_transforms.c. All other code was written from scratch. This encoder outperforms any other encoders in quality, usability and in features. Other existing implementations do not support 4 level transforms or 64x64 blocks (slices), which greatly increase compression. As previously said, the codec is meant for broadcasting, hence support for non-broadcasting image widths, heights, bit depths, aspect ratios, etc. are limited by the "level". Although this codec supports a few chroma subsamplings (420, 422, 444), signalling those is generally outside the specifications of the level used (3) and the reference decoder will outright refuse to read any image with such a flag signalled (it only supports 1920x1080 yuv422p10). However, most implementations will happily read files with alternate dimensions, framerates and formats signalled. Therefore, in order to encode files other than 1080p50 yuv422p10le, you need to provide an "-strict -2" argument to the command line. The FFmpeg decoder will happily read any files made with non-standard parameters, dimensions and subsamplings, and so will other implementations. IMO this should be "-strict -1", but I'll leave that up for discussion. There are still plenty of stuff to implement, for instance 5 more wavelet transforms are still in the specs and supported by the decoder. The encoder can be lossless, given a high enough bitrate. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-02-10 18:50:00 +02:00
/*
* Copyright (C) 2016 Open Broadcast Systems Ltd.
* Author 2016 Rostislav Pehlivanov <atomnuker@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
vc2enc: use project-standard inclusion guards This was first reported on the mailing list in an earlier revision of this encoder but was forgotten from the final commit. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-02-10 20:02:35 +02:00
#ifndef AVCODEC_VC2ENC_DWT_H
#define AVCODEC_VC2ENC_DWT_H
avcodec: add a native SMPTE VC-2 HQ encoder This commit adds a new encoder capable of creating BBC/SMPTE Dirac/VC-2 HQ profile files. Dirac is a wavelet based codec created by the BBC a little more than 10 years ago. Since then, wavelets have mostly gone out of style as they did not provide adequate encoding gains at lower bitrates. Dirac was a fully featured video codec equipped with perceptual masking, support for most popular pixel formats, interlacing, overlapped-block motion compensation, and other features. It found new life after being stripped of various features and standardized as the VC-2 codec by the SMPTE with an extra profile, the HQ profile that this encoder supports, added. The HQ profile was based off of the Low-Delay profile previously existing in Dirac. The profile forbids DC prediction and arithmetic coding to focus on high performance and low delay at higher bitrates. The standard bitrates for this profile vary but generally 1:4 compression is expected (~525 Mbps vs the 2200 Mbps for uncompressed 1080p50). The codec only supports I-frames, hence the high bitrates. The structure of this encoder is simple: do a DWT transform on the entire image, split it into multiple slices (specified by the user) and encode them in parallel. All of the slices are of the same size, making rate control and threading very trivial. Although only in C, this encoder is capable of 30 frames per second on an 4 core 8 threads Ivy Bridge. A lookup table is used to encode most of the coefficients. No code was used from the GSoC encoder from 2007 except for the 2 transform functions in diracenc_transforms.c. All other code was written from scratch. This encoder outperforms any other encoders in quality, usability and in features. Other existing implementations do not support 4 level transforms or 64x64 blocks (slices), which greatly increase compression. As previously said, the codec is meant for broadcasting, hence support for non-broadcasting image widths, heights, bit depths, aspect ratios, etc. are limited by the "level". Although this codec supports a few chroma subsamplings (420, 422, 444), signalling those is generally outside the specifications of the level used (3) and the reference decoder will outright refuse to read any image with such a flag signalled (it only supports 1920x1080 yuv422p10). However, most implementations will happily read files with alternate dimensions, framerates and formats signalled. Therefore, in order to encode files other than 1080p50 yuv422p10le, you need to provide an "-strict -2" argument to the command line. The FFmpeg decoder will happily read any files made with non-standard parameters, dimensions and subsamplings, and so will other implementations. IMO this should be "-strict -1", but I'll leave that up for discussion. There are still plenty of stuff to implement, for instance 5 more wavelet transforms are still in the specs and supported by the decoder. The encoder can be lossless, given a high enough bitrate. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-02-10 18:50:00 +02:00
avcodec/vc2enc_dwt: add missing header Fixes make checkheaders Signed-off-by: James Almer <jamrial@gmail.com>
2016-02-12 07:06:05 +02:00
#include <stddef.h>
avcodec: add a native SMPTE VC-2 HQ encoder This commit adds a new encoder capable of creating BBC/SMPTE Dirac/VC-2 HQ profile files. Dirac is a wavelet based codec created by the BBC a little more than 10 years ago. Since then, wavelets have mostly gone out of style as they did not provide adequate encoding gains at lower bitrates. Dirac was a fully featured video codec equipped with perceptual masking, support for most popular pixel formats, interlacing, overlapped-block motion compensation, and other features. It found new life after being stripped of various features and standardized as the VC-2 codec by the SMPTE with an extra profile, the HQ profile that this encoder supports, added. The HQ profile was based off of the Low-Delay profile previously existing in Dirac. The profile forbids DC prediction and arithmetic coding to focus on high performance and low delay at higher bitrates. The standard bitrates for this profile vary but generally 1:4 compression is expected (~525 Mbps vs the 2200 Mbps for uncompressed 1080p50). The codec only supports I-frames, hence the high bitrates. The structure of this encoder is simple: do a DWT transform on the entire image, split it into multiple slices (specified by the user) and encode them in parallel. All of the slices are of the same size, making rate control and threading very trivial. Although only in C, this encoder is capable of 30 frames per second on an 4 core 8 threads Ivy Bridge. A lookup table is used to encode most of the coefficients. No code was used from the GSoC encoder from 2007 except for the 2 transform functions in diracenc_transforms.c. All other code was written from scratch. This encoder outperforms any other encoders in quality, usability and in features. Other existing implementations do not support 4 level transforms or 64x64 blocks (slices), which greatly increase compression. As previously said, the codec is meant for broadcasting, hence support for non-broadcasting image widths, heights, bit depths, aspect ratios, etc. are limited by the "level". Although this codec supports a few chroma subsamplings (420, 422, 444), signalling those is generally outside the specifications of the level used (3) and the reference decoder will outright refuse to read any image with such a flag signalled (it only supports 1920x1080 yuv422p10). However, most implementations will happily read files with alternate dimensions, framerates and formats signalled. Therefore, in order to encode files other than 1080p50 yuv422p10le, you need to provide an "-strict -2" argument to the command line. The FFmpeg decoder will happily read any files made with non-standard parameters, dimensions and subsamplings, and so will other implementations. IMO this should be "-strict -1", but I'll leave that up for discussion. There are still plenty of stuff to implement, for instance 5 more wavelet transforms are still in the specs and supported by the decoder. The encoder can be lossless, given a high enough bitrate. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-02-10 18:50:00 +02:00
#include <stdint.h>
vc2enc_dwt: use 32 bit coefficients by default The problem is that with particularly complex images and especially at high bit depths and 5-level transforms the coefficients would overflow, causing huge artifacts to appear. This was discovered thanks to the fate tests, which will have to be redone as this fixes a multitude of problems and increases PSNR. There is a slight performance drop associated with this change, making the encoder slower by 1.15 times, however this is necessary in order to avoid undefined behavior and overflows. It would be worth to template the transforms to keep the performance for 8 bit images as 32 bit coefficients are unnecessary for that case, but the primary use of the encoder is to encode video at 10 bits. Reviewed-by: Christophe Gisquet <christophe.gisquet@gmail.com> Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-05-07 19:05:25 +02:00
typedef int32_t dwtcoef;
avcodec: add a native SMPTE VC-2 HQ encoder This commit adds a new encoder capable of creating BBC/SMPTE Dirac/VC-2 HQ profile files. Dirac is a wavelet based codec created by the BBC a little more than 10 years ago. Since then, wavelets have mostly gone out of style as they did not provide adequate encoding gains at lower bitrates. Dirac was a fully featured video codec equipped with perceptual masking, support for most popular pixel formats, interlacing, overlapped-block motion compensation, and other features. It found new life after being stripped of various features and standardized as the VC-2 codec by the SMPTE with an extra profile, the HQ profile that this encoder supports, added. The HQ profile was based off of the Low-Delay profile previously existing in Dirac. The profile forbids DC prediction and arithmetic coding to focus on high performance and low delay at higher bitrates. The standard bitrates for this profile vary but generally 1:4 compression is expected (~525 Mbps vs the 2200 Mbps for uncompressed 1080p50). The codec only supports I-frames, hence the high bitrates. The structure of this encoder is simple: do a DWT transform on the entire image, split it into multiple slices (specified by the user) and encode them in parallel. All of the slices are of the same size, making rate control and threading very trivial. Although only in C, this encoder is capable of 30 frames per second on an 4 core 8 threads Ivy Bridge. A lookup table is used to encode most of the coefficients. No code was used from the GSoC encoder from 2007 except for the 2 transform functions in diracenc_transforms.c. All other code was written from scratch. This encoder outperforms any other encoders in quality, usability and in features. Other existing implementations do not support 4 level transforms or 64x64 blocks (slices), which greatly increase compression. As previously said, the codec is meant for broadcasting, hence support for non-broadcasting image widths, heights, bit depths, aspect ratios, etc. are limited by the "level". Although this codec supports a few chroma subsamplings (420, 422, 444), signalling those is generally outside the specifications of the level used (3) and the reference decoder will outright refuse to read any image with such a flag signalled (it only supports 1920x1080 yuv422p10). However, most implementations will happily read files with alternate dimensions, framerates and formats signalled. Therefore, in order to encode files other than 1080p50 yuv422p10le, you need to provide an "-strict -2" argument to the command line. The FFmpeg decoder will happily read any files made with non-standard parameters, dimensions and subsamplings, and so will other implementations. IMO this should be "-strict -1", but I'll leave that up for discussion. There are still plenty of stuff to implement, for instance 5 more wavelet transforms are still in the specs and supported by the decoder. The encoder can be lossless, given a high enough bitrate. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-02-10 18:50:00 +02:00
enum VC2TransformType {
VC2_TRANSFORM_9_7 = 0, /* Deslauriers-Dubuc (9,7) */
VC2_TRANSFORM_5_3 = 1, /* LeGall (5,3) */
VC2_TRANSFORM_13_7 = 2, /* Deslauriers-Dubuc (13,7) */
VC2_TRANSFORM_HAAR = 3, /* Haar without shift */
VC2_TRANSFORM_HAAR_S = 4, /* Haar with 1 shift/lvl */
VC2_TRANSFORM_FIDEL = 5, /* Fidelity filter */
VC2_TRANSFORM_9_7_I = 6, /* Daubechies (9,7) */
VC2_TRANSFORMS_NB
};
typedef struct VC2TransformContext {
dwtcoef *buffer;
void (*vc2_subband_dwt[VC2_TRANSFORMS_NB])(struct VC2TransformContext *t,
dwtcoef *data, ptrdiff_t stride,
int width, int height);
} VC2TransformContext;
int ff_vc2enc_init_transforms(VC2TransformContext *t, int p_width, int p_height);
void ff_vc2enc_free_transforms(VC2TransformContext *t);
vc2enc: use project-standard inclusion guards This was first reported on the mailing list in an earlier revision of this encoder but was forgotten from the final commit. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-02-10 20:02:35 +02:00
#endif /* AVCODEC_VC2ENC_DWT_H */
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