[FFmpeg-devel,2/2] GSoC: Add guided filter

This version can be executed by thread in slice level.

To-Do-List:

1. Fast guided filter

2. Improve the derain/dehaze/denoise performance of guided filter

Signed-off-by: Xuewei Meng <928826483@qq.com>
---
 doc/filters.texi         |  21 +++
 libavfilter/Makefile     |   1 +
 libavfilter/allfilters.c |   1 +
 libavfilter/vf_guided.c  | 426 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 449 insertions(+)
 create mode 100644 libavfilter/vf_guided.c

Xuewei Meng <928826483@qq.com> 于2021年5月6日周四 下午10:59写道：
>
> This version can be executed by thread in slice level.
>
> To-Do-List:
>
> 1. Fast guided filter
>
> 2. Improve the derain/dehaze/denoise performance of guided filter
>
> Signed-off-by: Xuewei Meng <928826483@qq.com>
> ---
>  doc/filters.texi         |  21 +++
>  libavfilter/Makefile     |   1 +
>  libavfilter/allfilters.c |   1 +
>  libavfilter/vf_guided.c  | 426 +++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 449 insertions(+)
>  create mode 100644 libavfilter/vf_guided.c
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 36e35a1..d027ce9 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -12918,6 +12918,27 @@ greyedge=difford=1:minknorm=0:sigma=2
>
>  @end itemize
>
> +@section guided filter
> +Apply guided filter for dehazing, deraining and denoising.
> +
> +The filter accepts the following options:
> +@table @option
> +@item radius
> +Set the radius in pixels.
> +Allowed range is 1 to 20. Default is 3.
> +
> +@item eps
> +Set regularization parameter.
> +Allowed range is 0 to 1. Default is 0.2.
> +
> +@item planes
> +Set planes to filter. Default is first only.
> +@end table
> +
> +@subsection Commands
> +
> +This filter supports the all above options as @ref{commands}.
> +
>  @anchor{haldclut}
>  @section haldclut
>
> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> index 5a28736..7091508 100644
> --- a/libavfilter/Makefile
> +++ b/libavfilter/Makefile
> @@ -284,6 +284,7 @@ OBJS-$(CONFIG_GBLUR_FILTER)                  += vf_gblur.o
>  OBJS-$(CONFIG_GEQ_FILTER)                    += vf_geq.o
>  OBJS-$(CONFIG_GRADFUN_FILTER)                += vf_gradfun.o
>  OBJS-$(CONFIG_GRAPHMONITOR_FILTER)           += f_graphmonitor.o
> +OBJS-$(CONFIG_GUIDED_FILTER)                 += vf_guided.o
>  OBJS-$(CONFIG_GREYEDGE_FILTER)               += vf_colorconstancy.o
>  OBJS-$(CONFIG_HALDCLUT_FILTER)               += vf_lut3d.o framesync.o
>  OBJS-$(CONFIG_HFLIP_FILTER)                  += vf_hflip.o
> diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> index 931d7db..962f656 100644
> --- a/libavfilter/allfilters.c
> +++ b/libavfilter/allfilters.c
> @@ -270,6 +270,7 @@ extern const AVFilter ff_vf_geq;
>  extern const AVFilter ff_vf_gradfun;
>  extern const AVFilter ff_vf_graphmonitor;
>  extern const AVFilter ff_vf_greyedge;
> +extern const AVFilter ff_vf_guided;
>  extern const AVFilter ff_vf_haldclut;
>  extern const AVFilter ff_vf_hflip;
>  extern const AVFilter ff_vf_histeq;
> diff --git a/libavfilter/vf_guided.c b/libavfilter/vf_guided.c
> new file mode 100644
> index 0000000..9a8aee5
> --- /dev/null
> +++ b/libavfilter/vf_guided.c
> @@ -0,0 +1,426 @@
> +/*
> + * Copyright (c) 2021 Xuewei Meng
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in all
> + * copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> + * SOFTWARE.
> + */
> +
> +#include "libavutil/imgutils.h"
> +#include "libavutil/opt.h"
> +#include "libavutil/pixdesc.h"
> +#include "avfilter.h"
> +#include "formats.h"
> +#include "framesync.h"
> +#include "internal.h"
> +#include "video.h"
> +
> +typedef struct GuidedContext {
> +    const AVClass *class;
> +    FFFrameSync fs;
> +
> +    int radius;
> +    float eps;
> +
> +    int planes;
> +
> +    int width;
> +    int height;
> +
> +    int nb_planes;
> +    int depth;
> +    int planewidth[4];
> +    int planeheight[4];
> +
> +    int (*box)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
> +} GuidedContext;
> +
> +#define OFFSET(x) offsetof(GuidedContext, x)
> +#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
> +
> +static const AVOption guided_options[] = {
> +    { "radius", "set radius",           OFFSET(radius), AV_OPT_TYPE_INT,   {.i64=3    },   1,  20, FLAGS },
> +    { "eps",    "set eps",              OFFSET(eps),    AV_OPT_TYPE_FLOAT, {.dbl=0.2  }, 0.0,   1, FLAGS },
> +    { "planes", "set planes to filter", OFFSET(planes), AV_OPT_TYPE_INT,   {.i64=1    },   0, 0xF, FLAGS },
> +    { NULL }
> +};
> +
> +typedef struct ThreadData {
> +    int width;
> +    int height;
> +    float *src;
> +    float *dst;
> +    int srcStride;
> +    int dstStride;
> +} ThreadData;
> +
> +AVFILTER_DEFINE_CLASS(guided);
> +
> +static int box(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
> +{
> +    GuidedContext *s = ctx->priv;
> +    ThreadData *t = arg;
> +
> +    const int width  = t->width;
> +    const int height = t->height;
> +    const int src_stride = t->srcStride;
> +    const int dst_stride = t->dstStride;
> +    const int slice_start = (height * jobnr) / nb_jobs;
> +    const int slice_end   = (height * (jobnr + 1)) / nb_jobs;
> +    const int radius = s->radius;
> +    const float *src = t->src;
> +    float *dst = t->dst;
> +
> +    int w;
> +    int numPix;
> +    w = (radius << 1) + 1;
> +    numPix = w * w;
> +    for (int i = slice_start;i < slice_end;i++) {
> +      for (int j = 0;j < width;j++) {
> +        float temp = 0.0;
> +        for (int row = -radius;row <= radius;row++) {
> +          for (int col = -radius;col <= radius;col++) {
> +            int x = i + row;
> +            int y = j + col;
> +            x = (x < slice_start) ? slice_start : (x >= slice_end ? slice_end - 1 : x);
> +            y = (y < 0) ? 0 : (y >= width ? width - 1 : y);
> +            temp += src[x * src_stride + y];
> +          }
> +        }
> +        dst[i * dst_stride + j] = temp / numPix;
> +      }
> +    }
> +    return 0;
> +}
> +
> +static int query_formats(AVFilterContext *ctx)
> +{
> +    static const enum AVPixelFormat pix_fmts[] = {
> +        AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV440P,
> +        AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
> +        AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUV420P,
> +        AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
> +        AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
> +        AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
> +        AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
> +        AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV440P12,
> +        AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
> +        AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
> +        AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA444P9,
> +        AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA444P10,
> +        AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
> +        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
> +        AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
> +        AV_PIX_FMT_GBRAP, AV_PIX_FMT_GBRAP10, AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GBRAP16,
> +        AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY9, AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14, AV_PIX_FMT_GRAY16,
> +        AV_PIX_FMT_NONE
> +    };
> +
> +    return ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
> +}
> +
> +static int config_input(AVFilterLink *inlink)
> +{
> +    AVFilterContext *ctx = inlink->dst;
> +    GuidedContext *s = ctx->priv;
> +    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
> +
> +    if (ctx->inputs[0]->w != ctx->inputs[1]->w ||
> +        ctx->inputs[0]->h != ctx->inputs[1]->h) {
> +        av_log(ctx, AV_LOG_ERROR, "Width and height of input videos must be same.\n");
> +        return AVERROR(EINVAL);
> +    }
> +    if (ctx->inputs[0]->format != ctx->inputs[1]->format) {
> +        av_log(ctx, AV_LOG_ERROR, "Inputs must be of same pixel format.\n");
> +        return AVERROR(EINVAL);
> +    }
> +
> +
> +    s->depth = desc->comp[0].depth;
> +    s->width = ctx->inputs[0]->w;
> +    s->height = ctx->inputs[0]->h;
> +
> +    s->planewidth[1]  = s->planewidth[2] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
> +    s->planewidth[0]  = s->planewidth[3] = inlink->w;
> +    s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
> +    s->planeheight[0] = s->planeheight[3] = inlink->h;
> +
> +    s->nb_planes = av_pix_fmt_count_planes(inlink->format);
> +    s->box = box;
> +    return 0;
> +}
> +
> +#define GUIDED(type, name)                                                              \
> +static int guided_##name(AVFilterContext *ctx, GuidedContext *s,                        \
> +                          const uint8_t *ssrc, const uint8_t *ssrcRef,                  \
> +                          uint8_t *ddst, int radius, float eps, int width, int height,  \
> +                          int src_stride, int src_ref_stride, int dst_stride)           \
> +{                                                                                       \
> +    type *dst = (type *)ddst;                                                           \
> +    const type *src = (const type *)ssrc;                                               \
> +    const type *srcRef = (const type *)ssrcRef;                                         \
> +                                                                                        \
> +    ThreadData t;                                                                       \
> +    const int nb_threads = ff_filter_get_nb_threads(ctx);                               \
> +    float *I;                                                                           \
> +    float *II;                                                                          \
> +    float *P;                                                                           \
> +    float *IP;                                                                          \
> +    float *meanI;                                                                       \
> +    float *meanII;                                                                      \
> +    float *meanP;                                                                       \
> +    float *meanIP;                                                                      \
> +    float *A;                                                                           \
> +    float *B;                                                                           \
> +    float *meanA;                                                                       \
> +    float *meanB;                                                                       \
> +                                                                                        \
> +    I      = av_calloc(width * height, sizeof(float));                                  \
> +    II     = av_calloc(width * height, sizeof(float));                                  \
> +    P      = av_calloc(width * height, sizeof(float));                                  \
> +    IP     = av_calloc(width * height, sizeof(float));                                  \
> +    meanI  = av_calloc(width * height, sizeof(float));                                  \
> +    meanII = av_calloc(width * height, sizeof(float));                                  \
> +    meanP  = av_calloc(width * height, sizeof(float));                                  \
> +    meanIP = av_calloc(width * height, sizeof(float));                                  \
> +                                                                                        \
> +    A      = av_calloc(width * height, sizeof(float));                                  \
> +    B      = av_calloc(width * height, sizeof(float));                                  \
> +    meanA  = av_calloc(width * height, sizeof(float));                                  \
> +    meanB  = av_calloc(width * height, sizeof(float));                                  \
> +                                                                                        \
> +    if (!I || !II || !P || !IP || !meanI || !meanII || !meanP ||                        \
> +        !meanIP || !A || !B || !meanA || !meanB)                                        \
what about use a label at the at of this block, and set ret =
AVERROR(ENOMEM), goto the label,
just make sure it can free all the memory which have been allocate successful.
> +        return AVERROR(ENOMEM);                                                         \
> +                                                                                        \
> +    for (int i = 0;i < height;i++) {                                                    \
> +      for (int j = 0;j < width;j++) {                                                   \
> +        int x = i * width + j;                                                          \
> +        I[x]  = src[i * src_stride + j];                                                \
> +        II[x] = src[i * src_stride + j] * src[i * src_stride + j];                      \
> +        P[x]  = srcRef[i * src_ref_stride + j];                                         \
> +        IP[x] = src[i * src_stride + j] * srcRef[i * src_ref_stride + j];               \
> +      }                                                                                 \
> +    }                                                                                   \
> +                                                                                        \
> +    t.width  = width;                                                                   \
> +    t.height = height;                                                                  \
> +    t.srcStride = width;                                                                \
> +    t.dstStride = width;                                                                \
> +    t.src = I;                                                                          \
> +    t.dst = meanI;                                                                      \
> +    ctx->internal->execute(ctx, s->box, &t, NULL, FFMIN(height, nb_threads));           \
> +    t.src = II;                                                                         \
> +    t.dst = meanII;                                                                     \
> +    ctx->internal->execute(ctx, s->box, &t, NULL, FFMIN(height, nb_threads));           \
> +    t.src = P;                                                                          \
> +    t.dst = meanP;                                                                      \
> +    ctx->internal->execute(ctx, s->box, &t, NULL, FFMIN(height, nb_threads));           \
> +    t.src = IP;                                                                         \
> +    t.dst = meanIP;                                                                     \
> +    ctx->internal->execute(ctx, s->box, &t, NULL, FFMIN(height, nb_threads));           \
> +                                                                                        \
> +    for (int i = 0;i < height;i++) {                                                    \
> +      for (int j = 0;j < width;j++) {                                                   \
> +        int x = i * width + j;                                                          \
> +        float varI = meanII[x] - (meanI[x] * meanI[x]);                                 \
> +        float covIP = meanIP[x] - (meanI[x] * meanP[x]);                                \
> +        A[x] = covIP / (varI + eps);                                                    \
> +        B[x] = meanP[x] - A[x] * meanI[x];                                              \
> +      }                                                                                 \
> +    }                                                                                   \
> +                                                                                        \
> +    t.src = A;                                                                          \
> +    t.dst = meanA;                                                                      \
> +    ctx->internal->execute(ctx, s->box, &t, NULL, FFMIN(height, nb_threads));           \
> +    t.src = B;                                                                          \
> +    t.dst = meanB;                                                                      \
> +    ctx->internal->execute(ctx, s->box, &t, NULL, FFMIN(height, nb_threads));           \
> +                                                                                        \
> +    for (int i = 0;i < height;i++) {                                                    \
> +      for (int j = 0;j < width;j++) {                                                   \
> +        int x = i * width + j;                                                          \
> +        dst[i * dst_stride + j] = meanA[x] * src[i * src_stride + j] + meanB[x];        \
> +      }                                                                                 \
> +    }                                                                                   \
add label here?
> +    av_freep(&I);                                                                       \
> +    av_freep(&II);                                                                      \
> +    av_freep(&P);                                                                       \
> +    av_freep(&IP);                                                                      \
> +    av_freep(&meanI);                                                                   \
> +    av_freep(&meanII);                                                                  \
> +    av_freep(&meanP);                                                                   \
> +    av_freep(&meanIP);                                                                  \
> +    av_freep(&A);                                                                       \
> +    av_freep(&B);                                                                       \
> +    av_freep(&meanA);                                                                   \
> +    av_freep(&meanB);                                                                   \
> +    return 0;                                                                           \
if use goto and set ret, maybe return ret is better than 0.
> +}
> +
> +GUIDED(uint8_t, byte)
> +GUIDED(uint16_t, word)
> +
> +static int process_frame(FFFrameSync *fs)
> +{
> +    AVFilterContext *ctx = fs->parent;
> +    GuidedContext *s = fs->opaque;
> +    AVFilterLink *outlink = ctx->outputs[0];
> +    AVFrame *out_frame = NULL, *main_frame = NULL, *ref_frame = NULL;
> +    int ret;
> +
> +    ret = ff_framesync_dualinput_get(fs, &main_frame, &ref_frame);
> +    if (ret < 0)
> +        return ret;
> +
> +    out_frame = ff_get_video_buffer(outlink, outlink->w, outlink->h);
> +    if (!out_frame) {
> +        av_frame_free(&main_frame);
> +        av_frame_free(&ref_frame);
> +        return AVERROR(ENOMEM);
> +    }
> +    av_frame_copy_props(out_frame, main_frame);
> +
> +    if (ctx->is_disabled || !ref_frame) {
> +        av_frame_copy_props(ref_frame, main_frame);
> +    }
> +
> +    for (int plane = 0; plane < s->nb_planes; plane++) {
> +        if (!(s->planes & (1 << plane))) {
> +            av_image_copy_plane(out_frame->data[plane], out_frame->linesize[plane],
> +                                main_frame->data[plane], main_frame->linesize[plane],
> +                                s->planewidth[plane] * ((s->depth + 7) / 8), s->planeheight[plane]);
> +            continue;
> +        }
> +        if (s->depth <= 8)
> +           guided_byte(ctx, s, main_frame->data[plane], ref_frame->data[plane], out_frame->data[plane], s->radius, s->eps,
> +                       s->planewidth[plane], s->planeheight[plane],
> +                       main_frame->linesize[plane], ref_frame->linesize[plane], out_frame->linesize[plane]);
> +        else
> +           guided_word(ctx, s, main_frame->data[plane], ref_frame->data[plane], out_frame->data[plane], s->radius, s->eps,
> +                       s->planewidth[plane], s->planeheight[plane],
> +                       main_frame->linesize[plane] / 2, ref_frame->linesize[plane] / 2, out_frame->linesize[plane] / 2);
> +    }
> +
> +    return ff_filter_frame(outlink, out_frame);
> +}
> +
> +
> +static int config_output(AVFilterLink *outlink)
> +{
> +    AVFilterContext *ctx = outlink->src;
> +
> +    GuidedContext *s = ctx->priv;
> +    AVFilterLink *mainlink = ctx->inputs[0];
> +    FFFrameSyncIn *in;
> +    int ret;
> +
> +
> +    outlink->w = mainlink->w;
> +    outlink->h = mainlink->h;
> +    outlink->time_base = mainlink->time_base;
> +    outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
> +    outlink->frame_rate = mainlink->frame_rate;
> +    if ((ret = ff_framesync_init(&s->fs, ctx, 2)) < 0)
> +        return ret;
> +
> +    outlink->time_base = s->fs.time_base;
> +
> +    in = s->fs.in;
> +    in[0].time_base = mainlink->time_base;
> +    in[1].time_base = ctx->inputs[1]->time_base;
> +    in[0].sync   = 2;
> +    in[0].before = EXT_INFINITY;
> +    in[0].after  = EXT_INFINITY;
> +    in[1].sync   = 1;
> +    in[1].before = EXT_INFINITY;
> +    in[1].after  = EXT_INFINITY;
> +    s->fs.opaque   = s;
> +    s->fs.on_event = process_frame;
> +
> +    return ff_framesync_configure(&s->fs);
> +}
> +
> +static int activate(AVFilterContext *ctx)
> +{
> +    GuidedContext *s = ctx->priv;
> +    return ff_framesync_activate(&s->fs);
> +}
> +
> +static av_cold int init(AVFilterContext *ctx)
> +{
> +    return 0;
> +}
> +
> +static av_cold void uninit(AVFilterContext *ctx)
> +{
> +    GuidedContext *s = ctx->priv;
> +    ff_framesync_uninit(&s->fs);
> +    return;
> +}
> +
> +
> +static int process_command(AVFilterContext *ctx,
> +                           const char *cmd,
> +                           const char *arg,
> +                           char *res,
> +                           int res_len,
> +                           int flags)
> +{
> +    int ret = ff_filter_process_command(ctx, cmd, arg, res, res_len, flags);
> +
> +    if (ret < 0)
> +        return ret;
> +
> +    return 0;
> +}
> +
> +static const AVFilterPad guided_inputs[] = {
> +    {
> +        .name         = "main",
> +        .type         = AVMEDIA_TYPE_VIDEO,
> +    },{
> +        .name         = "reference",
> +        .type         = AVMEDIA_TYPE_VIDEO,
> +        .config_props = config_input,
> +    },
> +    { NULL }
> +};
> +
> +static const AVFilterPad guided_outputs[] = {
> +    {
> +        .name = "default",
> +        .type = AVMEDIA_TYPE_VIDEO,
> +        .config_props  = config_output,
> +    },
> +    { NULL }
> +};
> +
> +AVFilter ff_vf_guided = {
> +    .name            = "guided",
> +    .description     = NULL_IF_CONFIG_SMALL("Apply Guided filter."),
> +    .init            = init,
> +    .uninit          = uninit,
> +    .query_formats   = query_formats,
> +    .priv_size       = sizeof(GuidedContext),
> +    .priv_class      = &guided_class,
> +    .activate        = activate,
> +    .inputs          = guided_inputs,
> +    .outputs         = guided_outputs,
> +    .flags           = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
> +    .process_command = process_command,
> +};
> --
> 1.9.1
>
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Thanks
Steven