[FFmpeg-devel] [PATCH] libavfilter: created a new filter that obtains the average peak signal-to-noise ratio (PSNR) of two input video files in YUV format.
Roger Pau Monné
roger.pau at entel.upc.edu
Tue Jun 7 14:03:36 CEST 2011
2011/6/7 Stefano Sabatini <stefano.sabatini-lala at poste.it>:
> On date Monday 2011-06-06 15:49:46 +0200, Roger Pau Monné encoded:
>> 2011/6/6 Stefano Sabatini <stefano.sabatini-lala at poste.it>:
>> > On date Sunday 2011-06-05 21:00:35 +0200, Roger Pau Monn� encoded:
>> >>
>> >> Signed-off-by: Roger Pau Monn? <roger.pau at entel.upc.edu>
>> >> ---
>> >> libavfilter/vf_psnr.c | 272 +++++++++++++++++++++++++++++++++++++++++++++++++
>> >> 1 files changed, 272 insertions(+), 0 deletions(-)
>> >> create mode 100644 libavfilter/vf_psnr.c
>> >>
>> >> diff --git a/libavfilter/vf_psnr.c b/libavfilter/vf_psnr.c
>> >> new file mode 100644
>> >> index 0000000..c6a0b78
>> >> --- /dev/null
>> >> +++ b/libavfilter/vf_psnr.c
>> >> @@ -0,0 +1,272 @@
>> >> +/*
>> >> + * Copyright (c) 2011 Roger Pau Monné <roger.pau at entel.upc.edu>
>> >> + *
>> >> + * 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
>> >> + */
>> >> +
>> >> +/**
>> >> + * @file
>> >> + * Caculate the PSNR between two input videos
>> >> + * Based on the overlay filter
>> >> + */
>> >> +
>> >> +#include "libavutil/pixdesc.h"
>> >> +#include "avfilter.h"
>> >> +
>> >> +#undef fprintf
>> >> +
>> >> +typedef struct {
>> >> + AVFilterBufferRef *picref;
>> >> + double mse, min_mse, max_mse;
>> >> + int nb_frames;
>> >> + FILE *vstats_file;
>> >> + uint16_t *line1, *line2;
>> >> +} PSNRContext;
>> >> +
>> >> +static inline int pow2(int base)
>> >> +{
>> >> + return base*base;
>> >> +}
>> >> +
>> >> +static inline double psnr(double mse, int nb_frames, int max)
>> >> +{
>> >> + return 10.0*log((pow2(max))/(mse/nb_frames))/log(10.0);
>> >> +}
>> >> +
>> >> +static inline void av_compute_images_mse(const uint8_t *ref_data[4], const uint8_t *data[4], const int linesizes[4],
>> >> + int w, int h, const AVPixFmtDescriptor *desc, double mse[4], uint16_t *line1,
>> >> + uint16_t *line2)
>> >
>> > av_ is not required
>> >
>> >> +{
>> >> + int i, c, j = w;
>> >> +
>> >> + memset(mse, 0, sizeof(*mse)*4);
>> >> +
>> >> + for (c = 0; c < desc->nb_components; c++) {
>> >> + int w1 = c == 1 || c == 2 ? w>>desc->log2_chroma_w : w;
>> >> + int h1 = c == 1 || c == 2 ? h>>desc->log2_chroma_h : h;
>> >> +
>> >> + for (i = 0; i < h1; i++) {
>> >> + av_read_image_line(line1,
>> >> + ref_data,
>> >> + linesizes,
>> >> + desc,
>> >> + 0, i, c, w1, 0);
>> >> + av_read_image_line(line2,
>> >> + data,
>> >> + linesizes,
>> >> + desc,
>> >> + 0, i, c, w1, 0);
>> >> + for(j = 0; j < w1; j++)
>> >> + mse[c] += pow2(line1[j] - line2[j]);
>> >> + }
>> >> + mse[c] /= w1*h1;
>> >> + }
>> >> +}
>> >> +
>> >> +
>> >> +static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
>> >> +{
>> >> + PSNRContext *psnr_context = ctx->priv;
>> >
>> > You can only use "psnr" here and below and save some chars, as it is
>> > done in the other filters (and move psnr() -> get_psnr() or
>> > compute_psnr()).
>> >
>> >> +
>> >> + psnr_context->mse = psnr_context->nb_frames = 0;
>> >> + psnr_context->min_mse = psnr_context->max_mse = -1.0;
>> >> + psnr_context->picref = NULL;
>> >> +
>> >> + if (args != NULL && strlen(args) > 0) {
>> >> + psnr_context->vstats_file = fopen(args, "w");
>> >> + if (!psnr_context->vstats_file) {
>> >> + av_log(ctx, AV_LOG_ERROR, "Could not open stats file %s\n", args);
>> >
>> > Here you can use strerr(errno) for improving feedback:
>> > av_log(ctx, AV_LOG_ERROR, "Could not open stats file %s: %s\n", args, strerror(errno);
>> >
>> >> + return AVERROR(EINVAL);
>> >> + }
>> >> + }
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >> +static av_cold void uninit(AVFilterContext *ctx)
>> >> +{
>> >> + PSNRContext *psnr_context = ctx->priv;
>> >> +
>> >> + av_log(ctx, AV_LOG_INFO, "PSNR average:%0.2fdB min:%0.2fdB max:%0.2fdB\n",
>> >> + psnr(psnr_context->mse, psnr_context->nb_frames, 255),
>> >> + psnr(psnr_context->max_mse, 1, 255),
>> >> + psnr(psnr_context->min_mse, 1, 255));
>> >> +
>> >> + if (psnr_context->picref) {
>> >> + avfilter_unref_buffer(psnr_context->picref);
>> >> + psnr_context->picref = NULL;
>> >> + }
>> >
>> >> + if (psnr_context->line1)
>> >> + av_free(psnr_context->line1);
>> >> + if (psnr_context->line2)
>> >> + av_free(psnr_context->line2);
>> >
>> > av_freep
>> >
>> >> + if (psnr_context->vstats_file)
>> >> + fclose(psnr_context->vstats_file);
>> >> +}
>> >> +
>> >> +static int config_input_ref(AVFilterLink *inlink)
>> >> +{
>> >> + AVFilterContext *ctx = inlink->dst;
>> >> + PSNRContext *psnr_context = ctx->priv;
>> >> +
>> >> + 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/or heigth of input videos are different, could not calculate PSNR\n");
>> >> + return AVERROR(EINVAL);
>> >> + }
>> >> + if (ctx->inputs[0]->format != ctx->inputs[1]->format) {
>> >> + av_log(ctx, AV_LOG_ERROR, "Input filters have different pixel formats, could not calculate PSNR\n");
>> >> + return AVERROR(EINVAL);
>> >> + }
>> >> +
>> >> + if (!(psnr_context->line1 = av_malloc(sizeof(*psnr_context->line1) * inlink->w)) || !(psnr_context->line2 = av_malloc(sizeof(*psnr_context->line2) * inlink->w)))
>> >> + return AVERROR(ENOMEM);
>> >> +
>> >
>> >> + av_log(ctx, AV_LOG_INFO, "PSNR filter started correctly\n");
>> >
>> > please remove this
>> >
>> >> +
>> >> + return 0;
>> >> +}
>> >> +
>> >
>> >> +static int config_output(AVFilterLink *outlink)
>> >> +{
>> >> + AVFilterContext *ctx = outlink->src;
>> >> +
>> >> + outlink->time_base = outlink->src->inputs[0]->time_base;
>> >> + outlink->w = ctx->inputs[0]->w;
>> >> + outlink->h = ctx->inputs[0]->h;
>> >> + return 0;
>> >> +}
>> >
>> > This should not be required IIRC.
>> >
>> >> +
>> >> +static int query_formats(AVFilterContext *ctx)
>> >> +{
>> >> + static const enum PixelFormat pix_fmts[] = {
>> >> + PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P,
>> >> + PIX_FMT_YUV411P, PIX_FMT_YUV410P,
>> >> + PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P,
>> >> + PIX_FMT_YUV440P, PIX_FMT_YUVJ440P
>
> Missing trailing PIX_FMT_NONE, that was causing weird crashes.
>
>> >> + };
>> >> +
>> >> + avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
>> >> +
>> >> + return 0;
>> >
>> > Would be feasible to extend the filter to all formats? compute_images_mse()
>> > should be generic enough, and you would only need to set the max
>> > value. Anyway this should not block the patch.
>>
>
>> I'm not sure about how to obtain the max value of pixel formats, if
>> someone knows it, I will gladly expand the filter to compute the PSNR
>> for other formats.
>
> We don't have this information, but we need to get it from each filter
> (check for example my recently posted lut filter).
Done! Added support for RGB formats.
>
> [...]
> + at section psnr
> +
> +Obtain the PSNR between two input videos. Both video files must have
> +the same resolution and pixel format for this filter to work correctly.
>
> It is not clear what the output is, and also where and how the PSNR
> is computed and printed.
>
> +
> + at table @option
> + at item vstats
> +file used to save the PSNR of each individual frame (optional).
>
> This filter accepts a parameter which specifies the file ...
> If not specified the filter will not print any file.
>
> +
> +For example:
> + at example
> +movie=ref_movie.mpg, setpts=PTS-STARTPTS [ref]; [in] setpts=PTS-STARTPTS,
> +[ref] psnr=stats.log [out]
> + at end example
>
> Add some words for describing what this filterchain accomplishes.
> [...]
>
> I'm attaching an edited version of your patch with some nits addressed
> (mainly style fixes), please continue to edit on this version.
I've extended the info about the filter and explained the example.
> --
> FFmpeg = Freak Formidable Mastodontic Portable Efficient Guide
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-libavfilter-created-a-new-filter-that-obtains-the-av.patch
Type: application/octet-stream
Size: 15611 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20110607/7c9d5a81/attachment.obj>
More information about the ffmpeg-devel
mailing list