@@ -35,6 +35,7 @@ typedef struct HistogramContext {

     int            histogram_size;

     int            mult;

     int            ncomp;

+    int            dncomp;

     uint8_t        bg_color[4];

     uint8_t        fg_color[4];

     int            level_height;

@@ -236,6 +237,7 @@ static int config_output(AVFilterLink *outlink)

     outlink->h = (h->level_height + h->scale_height) * FFMAX(ncomp * h->display_mode, 1);

     h->odesc = av_pix_fmt_desc_get(outlink->format);

+    h->dncomp = h->odesc->nb_components;

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

     return 0;

@@ -319,7 +321,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)

             if (h->histogram_size <= 256) {

                 for (j = h->level_height - 1; j >= col_height; j--) {

                     if (h->display_mode) {

-                        for (l = 0; l < h->ncomp; l++)

+                        for (l = 0; l < h->dncomp; l++)

                             out->data[l][(j + start) * out->linesize[l] + i] = h->fg_color[l];

                     } else {

                         out->data[p][(j + start) * out->linesize[p] + i] = 255;

@@ -332,7 +334,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)

                 for (j = h->level_height - 1; j >= col_height; j--) {

                     if (h->display_mode) {

-                        for (l = 0; l < h->ncomp; l++)

+                        for (l = 0; l < h->dncomp; l++)

                             AV_WN16(out->data[l] + (j + start) * out->linesize[l] + i * 2, h->fg_color[l] * mult);

                     } else {

                         AV_WN16(out->data[p] + (j + start) * out->linesize[p] + i * 2, 255 * mult);