/*
  * Copyright (c) 2013 Paul B Mahol
  *
  * 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
  */
 
 #include "libavutil/opt.h"
 #include "avfilter.h"
 #include "drawutils.h"
 #include "formats.h"
 #include "internal.h"
 #include "video.h"
 
 #define R 0
 #define G 1
 #define B 2
 #define A 3
 

 typedef struct ColorChannelMixerContext {

     const AVClass *class;
     double rr, rg, rb, ra;
     double gr, gg, gb, ga;
     double br, bg, bb, ba;
     double ar, ag, ab, aa;
 
     int *lut[4][4];
 
     int *buffer;
 
     uint8_t rgba_map[4];
 } ColorChannelMixerContext;
 
 #define OFFSET(x) offsetof(ColorChannelMixerContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 static const AVOption colorchannelmixer_options[] = {
     { "rr", "set the red gain for the red channel",     OFFSET(rr), AV_OPT_TYPE_DOUBLE, {.dbl=1}, -2, 2, FLAGS },
     { "rg", "set the green gain for the red channel",   OFFSET(rg), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "rb", "set the blue gain for the red channel",    OFFSET(rb), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "ra", "set the alpha gain for the red channel",   OFFSET(ra), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "gr", "set the red gain for the green channel",   OFFSET(gr), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "gg", "set the green gain for the green channel", OFFSET(gg), AV_OPT_TYPE_DOUBLE, {.dbl=1}, -2, 2, FLAGS },
     { "gb", "set the blue gain for the green channel",  OFFSET(gb), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "ga", "set the alpha gain for the green channel", OFFSET(ga), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "br", "set the red gain for the blue channel",    OFFSET(br), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "bg", "set the green gain for the blue channel",  OFFSET(bg), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "bb", "set the blue gain for the blue channel",   OFFSET(bb), AV_OPT_TYPE_DOUBLE, {.dbl=1}, -2, 2, FLAGS },
     { "ba", "set the alpha gain for the blue channel",  OFFSET(ba), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "ar", "set the red gain for the alpha channel",   OFFSET(ar), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "ag", "set the green gain for the alpha channel", OFFSET(ag), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "ab", "set the blue gain for the alpha channel",  OFFSET(ab), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -2, 2, FLAGS },
     { "aa", "set the alpha gain for the alpha channel", OFFSET(aa), AV_OPT_TYPE_DOUBLE, {.dbl=1}, -2, 2, FLAGS },
     { NULL }
 };
 
 AVFILTER_DEFINE_CLASS(colorchannelmixer);
 
 static int query_formats(AVFilterContext *ctx)
 {
     static const enum AVPixelFormat pix_fmts[] = {
         AV_PIX_FMT_RGB24,  AV_PIX_FMT_BGR24,
         AV_PIX_FMT_RGBA,   AV_PIX_FMT_BGRA,
         AV_PIX_FMT_ARGB,   AV_PIX_FMT_ABGR,
         AV_PIX_FMT_0RGB,   AV_PIX_FMT_0BGR,
         AV_PIX_FMT_RGB0,   AV_PIX_FMT_BGR0,
         AV_PIX_FMT_RGB48,  AV_PIX_FMT_BGR48,
         AV_PIX_FMT_RGBA64, AV_PIX_FMT_BGRA64,
         AV_PIX_FMT_NONE
     };
 

     AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
     if (!fmts_list)
         return AVERROR(ENOMEM);
     return ff_set_common_formats(ctx, fmts_list);

 }
 
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;

     ColorChannelMixerContext *s = ctx->priv;

     int i, j, size, *buffer;
 

     ff_fill_rgba_map(s->rgba_map, outlink->format);

     switch (outlink->format) {
     case AV_PIX_FMT_RGB48:
     case AV_PIX_FMT_BGR48:
     case AV_PIX_FMT_RGBA64:
     case AV_PIX_FMT_BGRA64:
         size = 65536;
         break;
     default:
         size = 256;
     }
 

     s->buffer = buffer = av_malloc(16 * size * sizeof(*s->buffer));
     if (!s->buffer)

         return AVERROR(ENOMEM);
 
     for (i = 0; i < 4; i++)
         for (j = 0; j < 4; j++, buffer += size)

             s->lut[i][j] = buffer;

 
     for (i = 0; i < size; i++) {

         s->lut[R][R][i] = lrint(i * s->rr);
         s->lut[R][G][i] = lrint(i * s->rg);
         s->lut[R][B][i] = lrint(i * s->rb);
         s->lut[R][A][i] = lrint(i * s->ra);
 
         s->lut[G][R][i] = lrint(i * s->gr);
         s->lut[G][G][i] = lrint(i * s->gg);
         s->lut[G][B][i] = lrint(i * s->gb);
         s->lut[G][A][i] = lrint(i * s->ga);
 
         s->lut[B][R][i] = lrint(i * s->br);
         s->lut[B][G][i] = lrint(i * s->bg);
         s->lut[B][B][i] = lrint(i * s->bb);
         s->lut[B][A][i] = lrint(i * s->ba);
 
         s->lut[A][R][i] = lrint(i * s->ar);
         s->lut[A][G][i] = lrint(i * s->ag);
         s->lut[A][B][i] = lrint(i * s->ab);
         s->lut[A][A][i] = lrint(i * s->aa);

     }
 
     return 0;
 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 {
     AVFilterContext *ctx = inlink->dst;

     ColorChannelMixerContext *s = ctx->priv;

     AVFilterLink *outlink = ctx->outputs[0];

     const uint8_t roffset = s->rgba_map[R];
     const uint8_t goffset = s->rgba_map[G];
     const uint8_t boffset = s->rgba_map[B];
     const uint8_t aoffset = s->rgba_map[A];

     const uint8_t *srcrow = in->data[0];
     uint8_t *dstrow;
     AVFrame *out;
     int i, j;
 
     if (av_frame_is_writable(in)) {
         out = in;
     } else {
         out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!out) {
             av_frame_free(&in);
             return AVERROR(ENOMEM);
         }
         av_frame_copy_props(out, in);
     }
 
     dstrow = out->data[0];
     switch (outlink->format) {
     case AV_PIX_FMT_BGR24:
     case AV_PIX_FMT_RGB24:
         for (i = 0; i < outlink->h; i++) {
             const uint8_t *src = srcrow;
             uint8_t *dst = dstrow;
 
             for (j = 0; j < outlink->w * 3; j += 3) {
                 const uint8_t rin = src[j + roffset];
                 const uint8_t gin = src[j + goffset];
                 const uint8_t bin = src[j + boffset];
 

                 dst[j + roffset] = av_clip_uint8(s->lut[R][R][rin] +
                                                  s->lut[R][G][gin] +
                                                  s->lut[R][B][bin]);
                 dst[j + goffset] = av_clip_uint8(s->lut[G][R][rin] +
                                                  s->lut[G][G][gin] +
                                                  s->lut[G][B][bin]);
                 dst[j + boffset] = av_clip_uint8(s->lut[B][R][rin] +
                                                  s->lut[B][G][gin] +
                                                  s->lut[B][B][bin]);

             }
 
             srcrow += in->linesize[0];
             dstrow += out->linesize[0];
         }
         break;
     case AV_PIX_FMT_0BGR:
     case AV_PIX_FMT_0RGB:
     case AV_PIX_FMT_BGR0:
     case AV_PIX_FMT_RGB0:
         for (i = 0; i < outlink->h; i++) {
             const uint8_t *src = srcrow;
             uint8_t *dst = dstrow;
 
             for (j = 0; j < outlink->w * 4; j += 4) {
                 const uint8_t rin = src[j + roffset];
                 const uint8_t gin = src[j + goffset];
                 const uint8_t bin = src[j + boffset];
 

                 dst[j + roffset] = av_clip_uint8(s->lut[R][R][rin] +
                                                  s->lut[R][G][gin] +
                                                  s->lut[R][B][bin]);
                 dst[j + goffset] = av_clip_uint8(s->lut[G][R][rin] +
                                                  s->lut[G][G][gin] +
                                                  s->lut[G][B][bin]);
                 dst[j + boffset] = av_clip_uint8(s->lut[B][R][rin] +
                                                  s->lut[B][G][gin] +
                                                  s->lut[B][B][bin]);

                 if (in != out)
                     dst[j + aoffset] = 0;
             }
 
             srcrow += in->linesize[0];
             dstrow += out->linesize[0];
         }
         break;
     case AV_PIX_FMT_ABGR:
     case AV_PIX_FMT_ARGB:
     case AV_PIX_FMT_BGRA:
     case AV_PIX_FMT_RGBA:
         for (i = 0; i < outlink->h; i++) {
             const uint8_t *src = srcrow;
             uint8_t *dst = dstrow;
 
             for (j = 0; j < outlink->w * 4; j += 4) {
                 const uint8_t rin = src[j + roffset];
                 const uint8_t gin = src[j + goffset];
                 const uint8_t bin = src[j + boffset];
                 const uint8_t ain = src[j + aoffset];
 

                 dst[j + roffset] = av_clip_uint8(s->lut[R][R][rin] +
                                                  s->lut[R][G][gin] +
                                                  s->lut[R][B][bin] +
                                                  s->lut[R][A][ain]);
                 dst[j + goffset] = av_clip_uint8(s->lut[G][R][rin] +
                                                  s->lut[G][G][gin] +
                                                  s->lut[G][B][bin] +
                                                  s->lut[G][A][ain]);
                 dst[j + boffset] = av_clip_uint8(s->lut[B][R][rin] +
                                                  s->lut[B][G][gin] +
                                                  s->lut[B][B][bin] +
                                                  s->lut[B][A][ain]);
                 dst[j + aoffset] = av_clip_uint8(s->lut[A][R][rin] +
                                                  s->lut[A][G][gin] +
                                                  s->lut[A][B][bin] +
                                                  s->lut[A][A][ain]);

             }
 
             srcrow += in->linesize[0];
             dstrow += out->linesize[0];
         }
         break;
     case AV_PIX_FMT_BGR48:
     case AV_PIX_FMT_RGB48:
         for (i = 0; i < outlink->h; i++) {
             const uint16_t *src = (const uint16_t *)srcrow;
             uint16_t *dst = (uint16_t *)dstrow;
 
             for (j = 0; j < outlink->w * 3; j += 3) {
                 const uint16_t rin = src[j + roffset];
                 const uint16_t gin = src[j + goffset];
                 const uint16_t bin = src[j + boffset];
 

                 dst[j + roffset] = av_clip_uint16(s->lut[R][R][rin] +
                                                   s->lut[R][G][gin] +
                                                   s->lut[R][B][bin]);
                 dst[j + goffset] = av_clip_uint16(s->lut[G][R][rin] +
                                                   s->lut[G][G][gin] +
                                                   s->lut[G][B][bin]);
                 dst[j + boffset] = av_clip_uint16(s->lut[B][R][rin] +
                                                   s->lut[B][G][gin] +
                                                   s->lut[B][B][bin]);

             }
 
             srcrow += in->linesize[0];
             dstrow += out->linesize[0];
         }
         break;
     case AV_PIX_FMT_BGRA64:
     case AV_PIX_FMT_RGBA64:
         for (i = 0; i < outlink->h; i++) {
             const uint16_t *src = (const uint16_t *)srcrow;
             uint16_t *dst = (uint16_t *)dstrow;
 
             for (j = 0; j < outlink->w * 4; j += 4) {
                 const uint16_t rin = src[j + roffset];
                 const uint16_t gin = src[j + goffset];
                 const uint16_t bin = src[j + boffset];
                 const uint16_t ain = src[j + aoffset];
 

                 dst[j + roffset] = av_clip_uint16(s->lut[R][R][rin] +
                                                   s->lut[R][G][gin] +
                                                   s->lut[R][B][bin] +
                                                   s->lut[R][A][ain]);
                 dst[j + goffset] = av_clip_uint16(s->lut[G][R][rin] +
                                                   s->lut[G][G][gin] +
                                                   s->lut[G][B][bin] +
                                                   s->lut[G][A][ain]);
                 dst[j + boffset] = av_clip_uint16(s->lut[B][R][rin] +
                                                   s->lut[B][G][gin] +
                                                   s->lut[B][B][bin] +
                                                   s->lut[B][A][ain]);
                 dst[j + aoffset] = av_clip_uint16(s->lut[A][R][rin] +
                                                   s->lut[A][G][gin] +
                                                   s->lut[A][B][bin] +
                                                   s->lut[A][A][ain]);

             }
 
             srcrow += in->linesize[0];
             dstrow += out->linesize[0];
         }
     }
 
     if (in != out)
         av_frame_free(&in);
     return ff_filter_frame(ctx->outputs[0], out);
 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {

     ColorChannelMixerContext *s = ctx->priv;

     av_freep(&s->buffer);

 }
 
 static const AVFilterPad colorchannelmixer_inputs[] = {
     {

         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,

     },
     { NULL }
 };
 
 static const AVFilterPad colorchannelmixer_outputs[] = {

     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .config_props = config_output,
     },
     { NULL }

 };
 

 AVFilter ff_vf_colorchannelmixer = {

     .name          = "colorchannelmixer",
     .description   = NULL_IF_CONFIG_SMALL("Adjust colors by mixing color channels."),
     .priv_size     = sizeof(ColorChannelMixerContext),
     .priv_class    = &colorchannelmixer_class,
     .uninit        = uninit,
     .query_formats = query_formats,
     .inputs        = colorchannelmixer_inputs,
     .outputs       = colorchannelmixer_outputs,

     .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,

 };