/*
  * 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
  */
 
 /**
  * @file

  * audio to video multimedia vectorscope filter

  */
 
 #include "libavutil/avassert.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "audio.h"
 #include "video.h"
 #include "internal.h"
 
 enum VectorScopeMode {
     LISSAJOUS,
     LISSAJOUS_XY,

     POLAR,

     MODE_NB,
 };
 

 enum VectorScopeDraw {
     DOT,
     LINE,
     DRAW_NB,
 };
 

 enum VectorScopeScale {
     LIN,
     SQRT,
     CBRT,
     LOG,
     SCALE_NB,
 };
 

 typedef struct AudioVectorScopeContext {
     const AVClass *class;
     AVFrame *outpicref;
     int w, h;
     int hw, hh;

     int mode;

     int draw;

     int scale;

     int contrast[4];
     int fade[4];

     double zoom;

     int swap;
     int mirror;

     unsigned prev_x, prev_y;

     AVRational frame_rate;
 } AudioVectorScopeContext;
 
 #define OFFSET(x) offsetof(AudioVectorScopeContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 static const AVOption avectorscope_options[] = {
     { "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=LISSAJOUS}, 0, MODE_NB-1, FLAGS, "mode" },
     { "m",    "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=LISSAJOUS}, 0, MODE_NB-1, FLAGS, "mode" },
     { "lissajous",    "", 0, AV_OPT_TYPE_CONST, {.i64=LISSAJOUS},    0, 0, FLAGS, "mode" },
     { "lissajous_xy", "", 0, AV_OPT_TYPE_CONST, {.i64=LISSAJOUS_XY}, 0, 0, FLAGS, "mode" },

     { "polar",        "", 0, AV_OPT_TYPE_CONST, {.i64=POLAR},        0, 0, FLAGS, "mode" },

     { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
     { "r",    "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },

     { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="400x400"}, 0, 0, FLAGS },
     { "s",    "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="400x400"}, 0, 0, FLAGS },

     { "rc", "set red contrast",   OFFSET(contrast[0]), AV_OPT_TYPE_INT, {.i64=40},  0, 255, FLAGS },

     { "gc", "set green contrast", OFFSET(contrast[1]), AV_OPT_TYPE_INT, {.i64=160}, 0, 255, FLAGS },

     { "bc", "set blue contrast",  OFFSET(contrast[2]), AV_OPT_TYPE_INT, {.i64=80},  0, 255, FLAGS },
     { "ac", "set alpha contrast", OFFSET(contrast[3]), AV_OPT_TYPE_INT, {.i64=255}, 0, 255, FLAGS },

     { "rf", "set red fade",       OFFSET(fade[0]), AV_OPT_TYPE_INT, {.i64=15}, 0, 255, FLAGS },
     { "gf", "set green fade",     OFFSET(fade[1]), AV_OPT_TYPE_INT, {.i64=10}, 0, 255, FLAGS },

     { "bf", "set blue fade",      OFFSET(fade[2]), AV_OPT_TYPE_INT, {.i64=5},  0, 255, FLAGS },
     { "af", "set alpha fade",     OFFSET(fade[3]), AV_OPT_TYPE_INT, {.i64=5},  0, 255, FLAGS },

     { "zoom", "set zoom factor",  OFFSET(zoom), AV_OPT_TYPE_DOUBLE, {.dbl=1},  0, 10, FLAGS },

     { "draw", "set draw mode", OFFSET(draw), AV_OPT_TYPE_INT, {.i64=DOT}, 0, DRAW_NB-1, FLAGS, "draw" },
     { "dot",   "", 0, AV_OPT_TYPE_CONST, {.i64=DOT} , 0, 0, FLAGS, "draw" },
     { "line",  "", 0, AV_OPT_TYPE_CONST, {.i64=LINE}, 0, 0, FLAGS, "draw" },

     { "scale", "set amplitude scale mode", OFFSET(scale), AV_OPT_TYPE_INT, {.i64=LIN}, 0, SCALE_NB-1, FLAGS, "scale" },
     { "lin",   "linear",      0, AV_OPT_TYPE_CONST, {.i64=LIN},  0, 0, FLAGS, "scale" },
     { "sqrt",  "square root", 0, AV_OPT_TYPE_CONST, {.i64=SQRT}, 0, 0, FLAGS, "scale" },
     { "cbrt",  "cube root",   0, AV_OPT_TYPE_CONST, {.i64=CBRT}, 0, 0, FLAGS, "scale" },
     { "log",   "logarithmic", 0, AV_OPT_TYPE_CONST, {.i64=LOG},  0, 0, FLAGS, "scale" },

     { "swap", "swap x axis with y axis", OFFSET(swap), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
     { "mirror", "mirror axis", OFFSET(mirror), AV_OPT_TYPE_INT, {.i64=2}, 0, 3, FLAGS, "mirror" },
     { "none",  "no mirror", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "mirror" },
     { "x",  "mirror x",     0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "mirror" },
     { "y",  "mirror y",     0, AV_OPT_TYPE_CONST, {.i64=2}, 0, 0, FLAGS, "mirror" },
     { "xy", "mirror both",  0, AV_OPT_TYPE_CONST, {.i64=3}, 0, 0, FLAGS, "mirror" },

     { NULL }

 };
 
 AVFILTER_DEFINE_CLASS(avectorscope);
 

 static void draw_dot(AudioVectorScopeContext *s, unsigned x, unsigned y)

 {

     const int linesize = s->outpicref->linesize[0];

     uint8_t *dst;
 

     if (s->zoom > 1) {
         if (y >= s->h || x >= s->w)

             return;
     } else {

         y = FFMIN(y, s->h - 1);
         x = FFMIN(x, s->w - 1);

     }
 

     dst = &s->outpicref->data[0][y * linesize + x * 4];
     dst[0] = FFMIN(dst[0] + s->contrast[0], 255);
     dst[1] = FFMIN(dst[1] + s->contrast[1], 255);
     dst[2] = FFMIN(dst[2] + s->contrast[2], 255);

     dst[3] = FFMIN(dst[3] + s->contrast[3], 255);

 }
 

 static void draw_line(AudioVectorScopeContext *s, int x0, int y0, int x1, int y1)
 {
     int dx = FFABS(x1-x0), sx = x0 < x1 ? 1 : -1;
     int dy = FFABS(y1-y0), sy = y0 < y1 ? 1 : -1;
     int err = (dx>dy ? dx : -dy) / 2, e2;
 
     for (;;) {
         draw_dot(s, x0, y0);
 
         if (x0 == x1 && y0 == y1)
             break;
 
         e2 = err;
 
         if (e2 >-dx) {
             err -= dy;
             x0 += sx;
         }
 
         if (e2 < dy) {
             err += dx;
             y0 += sy;
         }
     }
 }
 

 static void fade(AudioVectorScopeContext *s)

 {

     const int linesize = s->outpicref->linesize[0];

     int i, j;
 

     if (s->fade[0] || s->fade[1] || s->fade[2]) {
         uint8_t *d = s->outpicref->data[0];
         for (i = 0; i < s->h; i++) {
             for (j = 0; j < s->w*4; j+=4) {
                 d[j+0] = FFMAX(d[j+0] - s->fade[0], 0);
                 d[j+1] = FFMAX(d[j+1] - s->fade[1], 0);
                 d[j+2] = FFMAX(d[j+2] - s->fade[2], 0);

                 d[j+3] = FFMAX(d[j+3] - s->fade[3], 0);

             }
             d += linesize;
         }
     }
 }
 
 static int query_formats(AVFilterContext *ctx)
 {
     AVFilterFormats *formats = NULL;
     AVFilterChannelLayouts *layout = NULL;
     AVFilterLink *inlink = ctx->inputs[0];
     AVFilterLink *outlink = ctx->outputs[0];
     static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_NONE };
     static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE };

     int ret;

 
     formats = ff_make_format_list(sample_fmts);

     if ((ret = ff_formats_ref         (formats, &inlink->out_formats        )) < 0 ||
         (ret = ff_add_channel_layout  (&layout, AV_CH_LAYOUT_STEREO         )) < 0 ||
         (ret = ff_channel_layouts_ref (layout , &inlink->out_channel_layouts)) < 0)
         return ret;

 
     formats = ff_all_samplerates();

     if ((ret = ff_formats_ref(formats, &inlink->out_samplerates)) < 0)
         return ret;

 
     formats = ff_make_format_list(pix_fmts);

     if ((ret = ff_formats_ref(formats, &outlink->in_formats)) < 0)
         return ret;

 
     return 0;
 }
 
 static int config_input(AVFilterLink *inlink)
 {
     AVFilterContext *ctx = inlink->dst;

     AudioVectorScopeContext *s = ctx->priv;

     int nb_samples;
 

     nb_samples = FFMAX(1024, ((double)inlink->sample_rate / av_q2d(s->frame_rate)) + 0.5);

     inlink->partial_buf_size =
     inlink->min_samples =
     inlink->max_samples = nb_samples;
 
     return 0;
 }
 
 static int config_output(AVFilterLink *outlink)
 {

     AudioVectorScopeContext *s = outlink->src->priv;

     outlink->w = s->w;
     outlink->h = s->h;

     outlink->sample_aspect_ratio = (AVRational){1,1};

     outlink->frame_rate = s->frame_rate;

     s->prev_x = s->hw = s->w / 2;

     s->prev_y = s->hh = s->mode == POLAR ? s->h - 1 : s->h / 2;

 
     return 0;
 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
 {
     AVFilterContext *ctx = inlink->dst;
     AVFilterLink *outlink = ctx->outputs[0];

     AudioVectorScopeContext *s = ctx->priv;
     const int hw = s->hw;
     const int hh = s->hh;

     unsigned x, y;

     unsigned prev_x = s->prev_x, prev_y = s->prev_y;

     double zoom = s->zoom;

     int i;
 

     if (!s->outpicref || s->outpicref->width  != outlink->w ||
                          s->outpicref->height != outlink->h) {
         av_frame_free(&s->outpicref);
         s->outpicref = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!s->outpicref) {

             av_frame_free(&insamples);
             return AVERROR(ENOMEM);

         }

         s->outpicref->sample_aspect_ratio = (AVRational){1,1};

         for (i = 0; i < outlink->h; i++)

             memset(s->outpicref->data[0] + i * s->outpicref->linesize[0], 0, outlink->w * 4);

     }

     s->outpicref->pts = insamples->pts;

     fade(s);

     if (zoom < 1) {
         float max = 0;
 
         switch (insamples->format) {
         case AV_SAMPLE_FMT_S16: {
             int16_t *samples = (int16_t *)insamples->data[0];
 
             for (i = 0; i < insamples->nb_samples * 2; i++) {
                 float sample = samples[i] / (float)INT16_MAX;
                 max = FFMAX(FFABS(sample), max);
             }
 
             }
             break;
         case AV_SAMPLE_FMT_FLT: {

             float *samples = (float *)insamples->data[0];

             for (i = 0; i < insamples->nb_samples * 2; i++) {

                 max = FFMAX(FFABS(samples[i]), max);
             }
             }
             break;
         default:
             av_assert2(0);
         }
 
         zoom = 1. / max;
     }
 

     for (i = 0; i < insamples->nb_samples; i++) {
         int16_t *samples = (int16_t *)insamples->data[0] + i * 2;
         float *samplesf = (float *)insamples->data[0] + i * 2;
         float src[2];

         switch (insamples->format) {
         case AV_SAMPLE_FMT_S16:
             src[0] = samples[0] / (float)INT16_MAX;
             src[1] = samples[1] / (float)INT16_MAX;
             break;
         case AV_SAMPLE_FMT_FLT:
             src[0] = samplesf[0];
             src[1] = samplesf[1];
             break;

         default:
             av_assert2(0);

         }
 

         switch (s->scale) {
         case SQRT:
             src[0] = FFSIGN(src[0]) * sqrtf(FFABS(src[0]));
             src[1] = FFSIGN(src[1]) * sqrtf(FFABS(src[1]));
             break;
         case CBRT:
             src[0] = FFSIGN(src[0]) * cbrtf(FFABS(src[0]));
             src[1] = FFSIGN(src[1]) * cbrtf(FFABS(src[1]));
             break;
         case LOG:
             src[0] = FFSIGN(src[0]) * logf(1 + FFABS(src[0])) / logf(2);
             src[1] = FFSIGN(src[1]) * logf(1 + FFABS(src[1])) / logf(2);
             break;
         }
 

         if (s->mirror & 1)
             src[0] = -src[0];
 
         if (s->mirror & 2)
             src[1] = -src[1];
 
         if (s->swap)
             FFSWAP(float, src[0], src[1]);;
 

         if (s->mode == LISSAJOUS) {
             x = ((src[1] - src[0]) * zoom / 2 + 1) * hw;
             y = (1.0 - (src[0] + src[1]) * zoom / 2) * hh;
         } else if (s->mode == LISSAJOUS_XY) {
             x = (src[1] * zoom + 1) * hw;
             y = (src[0] * zoom + 1) * hh;
         } else {
             float sx, sy, cx, cy;
 
             sx = src[1] * zoom;
             sy = src[0] * zoom;
             cx = sx * sqrtf(1 - 0.5 * sy * sy);
             cy = sy * sqrtf(1 - 0.5 * sx * sx);
             x = hw + hw * FFSIGN(cx + cy) * (cx - cy) * .7;
             y = s->h - s->h * fabsf(cx + cy) * .7;
         }
 
         if (s->draw == DOT) {
             draw_dot(s, x, y);
         } else {
             draw_line(s, x, y, prev_x, prev_y);

         }

         prev_x = x;
         prev_y = y;

     }
 

     s->prev_x = x, s->prev_y = y;

     av_frame_free(&insamples);
 

     return ff_filter_frame(outlink, av_frame_clone(s->outpicref));

 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {

     AudioVectorScopeContext *s = ctx->priv;

     av_frame_free(&s->outpicref);

 }
 
 static const AVFilterPad audiovectorscope_inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_AUDIO,
         .config_props = config_input,
         .filter_frame = filter_frame,
     },
     { NULL }
 };
 
 static const AVFilterPad audiovectorscope_outputs[] = {
     {

         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .config_props = config_output,

     },
     { NULL }
 };
 

 AVFilter ff_avf_avectorscope = {

     .name          = "avectorscope",

     .description   = NULL_IF_CONFIG_SMALL("Convert input audio to vectorscope video output."),

     .uninit        = uninit,
     .query_formats = query_formats,
     .priv_size     = sizeof(AudioVectorScopeContext),
     .inputs        = audiovectorscope_inputs,
     .outputs       = audiovectorscope_outputs,
     .priv_class    = &avectorscope_class,
 };