avfilter/avf_showwaves: color support

Signed-off-by: Paul B Mahol <onemda@gmail.com>

libavfilter/avf_showwaves.c

@@ -24,6 +24,7 @@
  */
 
 #include "libavutil/avassert.h"
+#include "libavutil/avstring.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
@@ -50,15 +51,18 @@ typedef struct {
     const AVClass *class;
     int w, h;
     AVRational rate;
+    char *colors;
     int buf_idx;
     int16_t *buf_idy;    /* y coordinate of previous sample for each channel */
     AVFrame *outpicref;
     int n;
+    int pixstep;
     int sample_count_mod;
     int mode;                   ///< ShowWavesMode
     int split_channels;
+    uint8_t *fg;
     void (*draw_sample)(uint8_t *buf, int height, int linesize,
-                        int16_t sample, int16_t *prev_y, int intensity);
+                        int16_t sample, int16_t *prev_y, const uint8_t color[4]);
 
     /* single picture */
     int single_pic;
@@ -83,6 +87,7 @@ static const AVOption showwaves_options[] = {
     { "rate", "set video rate", OFFSET(rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, FLAGS },
     { "r",    "set video rate", OFFSET(rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, FLAGS },
     { "split_channels", "draw channels separately", OFFSET(split_channels), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS },
+    { "colors", "set channels colors", OFFSET(colors), AV_OPT_TYPE_STRING, {.str = "red|green|blue|yellow|orange|lime|pink|magenta|brown" }, 0, 0, FLAGS },
     { NULL }
 };
 
@@ -94,6 +99,7 @@ static av_cold void uninit(AVFilterContext *ctx)
 
     av_frame_free(&showwaves->outpicref);
     av_freep(&showwaves->buf_idy);
+    av_freep(&showwaves->fg);
 
     if (showwaves->single_pic) {
         struct frame_node *node = showwaves->audio_frames;
@@ -116,7 +122,7 @@ static int query_formats(AVFilterContext *ctx)
     AVFilterLink *inlink = ctx->inputs[0];
     AVFilterLink *outlink = ctx->outputs[0];
     static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE };
-    static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
+    static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGBA, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
     int ret;
 
     /* set input audio formats */
@@ -140,12 +146,147 @@ static int query_formats(AVFilterContext *ctx)
     return 0;
 }
 
+static void draw_sample_point_rgba(uint8_t *buf, int height, int linesize,
+                                   int16_t sample, int16_t *prev_y,
+                                   const uint8_t color[4])
+{
+    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
+    if (h >= 0 && h < height) {
+        buf[h * linesize + 0] += color[0];
+        buf[h * linesize + 1] += color[1];
+        buf[h * linesize + 2] += color[2];
+        buf[h * linesize + 3] += color[3];
+    }
+}
+
+static void draw_sample_line_rgba(uint8_t *buf, int height, int linesize,
+                                  int16_t sample, int16_t *prev_y,
+                                  const uint8_t color[4])
+{
+    int k;
+    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
+    int start   = height/2;
+    int end     = av_clip(h, 0, height-1);
+    if (start > end)
+        FFSWAP(int16_t, start, end);
+    for (k = start; k < end; k++) {
+        buf[k * linesize + 0] += color[0];
+        buf[k * linesize + 1] += color[1];
+        buf[k * linesize + 2] += color[2];
+        buf[k * linesize + 3] += color[3];
+    }
+}
+
+static void draw_sample_p2p_rgba(uint8_t *buf, int height, int linesize,
+                                 int16_t sample, int16_t *prev_y,
+                                 const uint8_t color[4])
+{
+    int k;
+    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
+    if (h >= 0 && h < height) {
+        buf[h * linesize + 0] += color[0];
+        buf[h * linesize + 1] += color[1];
+        buf[h * linesize + 2] += color[2];
+        buf[h * linesize + 3] += color[3];
+        if (*prev_y && h != *prev_y) {
+            int start = *prev_y;
+            int end = av_clip(h, 0, height-1);
+            if (start > end)
+                FFSWAP(int16_t, start, end);
+            for (k = start + 1; k < end; k++) {
+                buf[k * linesize + 0] += color[0];
+                buf[k * linesize + 1] += color[1];
+                buf[k * linesize + 2] += color[2];
+                buf[k * linesize + 3] += color[3];
+            }
+        }
+    }
+    *prev_y = h;
+}
+
+static void draw_sample_cline_rgba(uint8_t *buf, int height, int linesize,
+                                   int16_t sample, int16_t *prev_y,
+                                   const uint8_t color[4])
+{
+    int k;
+    const int h     = av_rescale(abs(sample), height, INT16_MAX);
+    const int start = (height - h) / 2;
+    const int end   = start + h;
+    for (k = start; k < end; k++) {
+        buf[k * linesize + 0] += color[0];
+        buf[k * linesize + 1] += color[1];
+        buf[k * linesize + 2] += color[2];
+        buf[k * linesize + 3] += color[3];
+    }
+}
+
+static void draw_sample_point_gray(uint8_t *buf, int height, int linesize,
+                                   int16_t sample, int16_t *prev_y,
+                                   const uint8_t color[4])
+{
+    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
+    if (h >= 0 && h < height)
+        buf[h * linesize] += color[0];
+}
+
+static void draw_sample_line_gray(uint8_t *buf, int height, int linesize,
+                                  int16_t sample, int16_t *prev_y,
+                                  const uint8_t color[4])
+{
+    int k;
+    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
+    int start   = height/2;
+    int end     = av_clip(h, 0, height-1);
+    if (start > end)
+        FFSWAP(int16_t, start, end);
+    for (k = start; k < end; k++)
+        buf[k * linesize] += color[0];
+}
+
+static void draw_sample_p2p_gray(uint8_t *buf, int height, int linesize,
+                                 int16_t sample, int16_t *prev_y,
+                                 const uint8_t color[4])
+{
+    int k;
+    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
+    if (h >= 0 && h < height) {
+        buf[h * linesize] += color[0];
+        if (*prev_y && h != *prev_y) {
+            int start = *prev_y;
+            int end = av_clip(h, 0, height-1);
+            if (start > end)
+                FFSWAP(int16_t, start, end);
+            for (k = start + 1; k < end; k++)
+                buf[k * linesize] += color[0];
+        }
+    }
+    *prev_y = h;
+}
+
+static void draw_sample_cline_gray(uint8_t *buf, int height, int linesize,
+                                   int16_t sample, int16_t *prev_y,
+                                   const uint8_t color[4])
+{
+    int k;
+    const int h     = av_rescale(abs(sample), height, INT16_MAX);
+    const int start = (height - h) / 2;
+    const int end   = start + h;
+    for (k = start; k < end; k++)
+        buf[k * linesize] += color[0];
+}
+
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
     AVFilterLink *inlink = ctx->inputs[0];
     ShowWavesContext *showwaves = ctx->priv;
     int nb_channels = inlink->channels;
+    char *colors, *saveptr = NULL;
+    uint8_t x;
+    int ch;
+
+    if (showwaves->single_pic)
+        showwaves->n = 1;
 
     if (!showwaves->n)
         showwaves->n = FFMAX(1, ((double)inlink->sample_rate / (showwaves->w * av_q2d(showwaves->rate))) + 0.5);
@@ -164,6 +305,62 @@ static int config_output(AVFilterLink *outlink)
 
     av_log(ctx, AV_LOG_VERBOSE, "s:%dx%d r:%f n:%d\n",
            showwaves->w, showwaves->h, av_q2d(outlink->frame_rate), showwaves->n);
+
+    switch (outlink->format) {
+    case AV_PIX_FMT_GRAY8:
+        switch (showwaves->mode) {
+        case MODE_POINT:         showwaves->draw_sample = draw_sample_point_gray; break;
+        case MODE_LINE:          showwaves->draw_sample = draw_sample_line_gray;  break;
+        case MODE_P2P:           showwaves->draw_sample = draw_sample_p2p_gray;   break;
+        case MODE_CENTERED_LINE: showwaves->draw_sample = draw_sample_cline_gray; break;
+        default:
+            return AVERROR_BUG;
+        }
+        showwaves->pixstep = 1;
+        break;
+    case AV_PIX_FMT_RGBA:
+        switch (showwaves->mode) {
+        case MODE_POINT:         showwaves->draw_sample = draw_sample_point_rgba; break;
+        case MODE_LINE:          showwaves->draw_sample = draw_sample_line_rgba;  break;
+        case MODE_P2P:           showwaves->draw_sample = draw_sample_p2p_rgba;   break;
+        case MODE_CENTERED_LINE: showwaves->draw_sample = draw_sample_cline_rgba; break;
+        default:
+            return AVERROR_BUG;
+        }
+        showwaves->pixstep = 4;
+        break;
+    }
+
+    showwaves->fg = av_malloc_array(nb_channels, 4 * sizeof(*showwaves->fg));
+    if (!showwaves->fg)
+        return AVERROR(ENOMEM);
+
+    colors = av_strdup(showwaves->colors);
+    if (!colors)
+        return AVERROR(ENOMEM);
+
+    /* multiplication factor, pre-computed to avoid in-loop divisions */
+    x = 255 / ((showwaves->split_channels ? 1 : nb_channels) * showwaves->n);
+    if (outlink->format == AV_PIX_FMT_RGBA) {
+        uint8_t fg[4] = { 0xff, 0xff, 0xff, 0xff };
+
+        for (ch = 0; ch < nb_channels; ch++) {
+            char *color;
+
+            color = av_strtok(ch == 0 ? colors : NULL, " |", &saveptr);
+            if (color)
+                av_parse_color(fg, color, -1, ctx);
+            showwaves->fg[4*ch + 0] = fg[0] * x / 255.;
+            showwaves->fg[4*ch + 1] = fg[1] * x / 255.;
+            showwaves->fg[4*ch + 2] = fg[2] * x / 255.;
+            showwaves->fg[4*ch + 3] = fg[3] * x / 255.;
+        }
+    } else {
+        for (ch = 0; ch < nb_channels; ch++)
+            showwaves->fg[4 * ch + 0] = x;
+    }
+    av_free(colors);
+
     return 0;
 }
 
@@ -192,9 +389,9 @@ static int push_single_pic(AVFilterLink *outlink)
     AVFrame *out = showwaves->outpicref;
     struct frame_node *node;
     const int nb_channels = inlink->channels;
-    const int x = 255 / (showwaves->split_channels ? 1 : nb_channels);
     const int ch_height = showwaves->split_channels ? outlink->h / nb_channels : outlink->h;
     const int linesize = out->linesize[0];
+    const int pixstep = showwaves->pixstep;
     int col = 0;
     int64_t *sum = showwaves->sum;
 
@@ -220,11 +417,11 @@ static int push_single_pic(AVFilterLink *outlink)
             if (n++ == max_samples) {
                 for (ch = 0; ch < nb_channels; ch++) {
                     int16_t sample = sum[ch] / max_samples;
-                    uint8_t *buf = out->data[0] + col;
+                    uint8_t *buf = out->data[0] + col * pixstep;
                     if (showwaves->split_channels)
                         buf += ch*ch_height*linesize;
                     av_assert0(col < outlink->w);
-                    showwaves->draw_sample(buf, ch_height, linesize, sample, &showwaves->buf_idy[ch], x);
+                    showwaves->draw_sample(buf, ch_height, linesize, sample, &showwaves->buf_idy[ch], &showwaves->fg[ch * 4]);
                     sum[ch] = 0;
                 }
                 col++;
@@ -254,57 +451,6 @@ static int request_frame(AVFilterLink *outlink)
     return ret;
 }
 
-static void draw_sample_point(uint8_t *buf, int height, int linesize,
-                              int16_t sample, int16_t *prev_y, int intensity)
-{
-    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
-    if (h >= 0 && h < height)
-        buf[h * linesize] += intensity;
-}
-
-static void draw_sample_line(uint8_t *buf, int height, int linesize,
-                             int16_t sample, int16_t *prev_y, int intensity)
-{
-    int k;
-    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
-    int start   = height/2;
-    int end     = av_clip(h, 0, height-1);
-    if (start > end)
-        FFSWAP(int16_t, start, end);
-    for (k = start; k < end; k++)
-        buf[k * linesize] += intensity;
-}
-
-static void draw_sample_p2p(uint8_t *buf, int height, int linesize,
-                            int16_t sample, int16_t *prev_y, int intensity)
-{
-    int k;
-    const int h = height/2 - av_rescale(sample, height/2, INT16_MAX);
-    if (h >= 0 && h < height) {
-        buf[h * linesize] += intensity;
-        if (*prev_y && h != *prev_y) {
-            int start = *prev_y;
-            int end = av_clip(h, 0, height-1);
-            if (start > end)
-                FFSWAP(int16_t, start, end);
-            for (k = start + 1; k < end; k++)
-                buf[k * linesize] += intensity;
-        }
-    }
-    *prev_y = h;
-}
-
-static void draw_sample_cline(uint8_t *buf, int height, int linesize,
-                              int16_t sample, int16_t *prev_y, int intensity)
-{
-    int k;
-    const int h     = av_rescale(abs(sample), height, INT16_MAX);
-    const int start = (height - h) / 2;
-    const int end   = start + h;
-    for (k = start; k < end; k++)
-        buf[k * linesize] += intensity;
-}
-
 static int alloc_out_frame(ShowWavesContext *showwaves, const int16_t *p,
                            const AVFilterLink *inlink, AVFilterLink *outlink,
                            const AVFrame *in)
@@ -321,7 +467,7 @@ static int alloc_out_frame(ShowWavesContext *showwaves, const int16_t *p,
                                           av_make_q(1, inlink->sample_rate),
                                           outlink->time_base);
         for (j = 0; j < outlink->h; j++)
-            memset(out->data[0] + j*out->linesize[0], 0, outlink->w);
+            memset(out->data[0] + j*out->linesize[0], 0, outlink->w * showwaves->pixstep);
     }
     return 0;
 }
@@ -335,14 +481,6 @@ static av_cold int init(AVFilterContext *ctx)
         showwaves->mode = MODE_CENTERED_LINE;
     }
 
-    switch (showwaves->mode) {
-    case MODE_POINT:         showwaves->draw_sample = draw_sample_point; break;
-    case MODE_LINE:          showwaves->draw_sample = draw_sample_line;  break;
-    case MODE_P2P:           showwaves->draw_sample = draw_sample_p2p;   break;
-    case MODE_CENTERED_LINE: showwaves->draw_sample = draw_sample_cline; break;
-    default:
-        return AVERROR_BUG;
-    }
     return 0;
 }
 
@@ -358,8 +496,8 @@ static int showwaves_filter_frame(AVFilterLink *inlink, AVFrame *insamples)
     int16_t *p = (int16_t *)insamples->data[0];
     int nb_channels = inlink->channels;
     int i, j, ret = 0;
+    const int pixstep = showwaves->pixstep;
     const int n = showwaves->n;
-    const int x = 255 / ((showwaves->split_channels ? 1 : nb_channels) * n); /* multiplication factor, pre-computed to avoid in-loop divisions */
     const int ch_height = showwaves->split_channels ? outlink->h / nb_channels : outlink->h;
 
     /* draw data in the buffer */
@@ -371,12 +509,12 @@ static int showwaves_filter_frame(AVFilterLink *inlink, AVFrame *insamples)
         outpicref = showwaves->outpicref;
 
         for (j = 0; j < nb_channels; j++) {
-            uint8_t *buf = outpicref->data[0] + showwaves->buf_idx;
+            uint8_t *buf = outpicref->data[0] + showwaves->buf_idx * pixstep;
             const int linesize = outpicref->linesize[0];
             if (showwaves->split_channels)
                 buf += j*ch_height*linesize;
             showwaves->draw_sample(buf, ch_height, linesize, *p++,
-                                   &showwaves->buf_idy[j], x);
+                                   &showwaves->buf_idy[j], &showwaves->fg[j * 4]);
         }
 
         showwaves->sample_count_mod++;
@@ -437,6 +575,7 @@ static const AVOption showwavespic_options[] = {
     { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "600x240"}, 0, 0, FLAGS },
     { "s",    "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "600x240"}, 0, 0, FLAGS },
     { "split_channels", "draw channels separately", OFFSET(split_channels), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS },
+    { "colors", "set channels colors", OFFSET(colors), AV_OPT_TYPE_STRING, {.str = "red|green|blue|yellow|orange|lime|pink|magenta|brown" }, 0, 0, FLAGS },
     { NULL }
 };