From 1ffac25d31eb4aa7dd8680dbc5ae132007796e98 Mon Sep 17 00:00:00 2001 From: Werner Robitza Date: Mon, 10 Feb 2014 18:16:36 +0100 Subject: [PATCH] doc/filters/histogram: copyedit for grammar There were a few grammar and spelling mistakes in this filter description. I went through it and corrected them without changing the meaning. --- doc/filters.texi | 84 +++++++++++++++++++++++------------------------- 1 file changed, 40 insertions(+), 44 deletions(-) diff --git a/doc/filters.texi b/doc/filters.texi index 2639f8cf38..1d3c30b0d1 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -4937,8 +4937,8 @@ the histogram. Possible values are @code{none}, @code{weak} or Compute and draw a color distribution histogram for the input video. -The computed histogram is a representation of distribution of color components -in an image. +The computed histogram is a representation of the color component +distribution in an image. The filter accepts the following options: @@ -4949,41 +4949,38 @@ Set histogram mode. It accepts the following values: @table @samp @item levels -standard histogram that display color components distribution in an image. -Displays color graph for each color component. Shows distribution -of the Y, U, V, A or R, G, B components, depending on input format, -in current frame. Bellow each graph is color component scale meter. +Standard histogram that displays the color components distribution in an +image. Displays color graph for each color component. Shows distribution of +the Y, U, V, A or R, G, B components, depending on input format, in the +current frame. Below each graph a color component scale meter is shown. @item color -chroma values in vectorscope, if brighter more such chroma values are -distributed in an image. -Displays chroma values (U/V color placement) in two dimensional graph -(which is called a vectorscope). It can be used to read of the hue and -saturation of the current frame. At a same time it is a histogram. -The whiter a pixel in the vectorscope, the more pixels of the input frame -correspond to that pixel (that is the more pixels have this chroma value). -The V component is displayed on the horizontal (X) axis, with the leftmost -side being V = 0 and the rightmost side being V = 255. -The U component is displayed on the vertical (Y) axis, with the top -representing U = 0 and the bottom representing U = 255. +Displays chroma values (U/V color placement) in a two dimensional +graph (which is called a vectorscope). The brighter a pixel in the +vectorscope, the more pixels of the input frame correspond to that pixel +(i.e., more pixels have this chroma value). The V component is displayed on +the horizontal (X) axis, with the leftmost side being V = 0 and the rightmost +side being V = 255. The U component is displayed on the vertical (Y) axis, +with the top representing U = 0 and the bottom representing U = 255. -The position of a white pixel in the graph corresponds to the chroma value -of a pixel of the input clip. So the graph can be used to read of the -hue (color flavor) and the saturation (the dominance of the hue in the color). -As the hue of a color changes, it moves around the square. At the center of -the square, the saturation is zero, which means that the corresponding pixel -has no color. If you increase the amount of a specific color, while leaving -the other colors unchanged, the saturation increases, and you move towards +The position of a white pixel in the graph corresponds to the chroma value of +a pixel of the input clip. The graph can therefore be used to read the hue +(color flavor) and the saturation (the dominance of the hue in the color). As +the hue of a color changes, it moves around the square. At the center of the +square the saturation is zero, which means that the corresponding pixel has no +color. If the amount of a specific color is increased (while leaving the other +colors unchanged) the saturation increases, and the indicator moves towards the edge of the square. @item color2 -chroma values in vectorscope, similar as @code{color} but actual chroma values +Chroma values in vectorscope, similar as @code{color} but actual chroma values are displayed. @item waveform -per row/column color component graph. In row mode graph in the left side represents -color component value 0 and right side represents value = 255. In column mode top -side represents color component value = 0 and bottom side represents value = 255. +Per row/column color component graph. In row mode, the graph on the left side +represents color component value 0 and the right side represents value = 255. +In column mode, the top side represents color component value = 0 and bottom +side represents value = 255. @end table Default value is @code{levels}. @@ -4996,8 +4993,8 @@ Set height of color scale in @code{levels}. Default value is @code{12}. Allowed range is [0, 40]. @item step -Set step for @code{waveform} mode. Smaller values are useful to find out how much -of same luminance values across input rows/columns are distributed. +Set step for @code{waveform} mode. Smaller values are useful to find out how +many values of the same luminance are distributed across input rows/columns. Default value is @code{10}. Allowed range is [1, 255]. @item waveform_mode @@ -5016,26 +5013,25 @@ It accepts the following values: @table @samp @item parade Display separate graph for the color components side by side in -@code{row} waveform mode or one below other in @code{column} waveform mode -for @code{waveform} histogram mode. For @code{levels} histogram mode -per color component graphs are placed one bellow other. +@code{row} waveform mode or one below the other in @code{column} waveform mode +for @code{waveform} histogram mode. For @code{levels} histogram mode, +per color component graphs are placed below each other. -This display mode in @code{waveform} histogram mode makes it easy to spot -color casts in the highlights and shadows of an image, by comparing the -contours of the top and the bottom of each waveform. -Since whites, grays, and blacks are characterized by -exactly equal amounts of red, green, and blue, neutral areas of the -picture should display three waveforms of roughly equal width/height. -If not, the correction is easy to make by making adjustments to level the -three waveforms. +Using this display mode in @code{waveform} histogram mode makes it easy to +spot color casts in the highlights and shadows of an image, by comparing the +contours of the top and the bottom graphs of each waveform. Since whites, +grays, and blacks are characterized by exactly equal amounts of red, green, +and blue, neutral areas of the picture should display three waveforms of +roughly equal width/height. If not, the correction is easy to perform by +making level adjustments the three waveforms. @item overlay -Presents information that's identical to that in the @code{parade}, except +Presents information identical to that in the @code{parade}, except that the graphs representing color components are superimposed directly over one another. -This display mode in @code{waveform} histogram mode can make it easier to spot -the relative differences or similarities in overlapping areas of the color +This display mode in @code{waveform} histogram mode makes it easier to spot +relative differences or similarities in overlapping areas of the color components that are supposed to be identical, such as neutral whites, grays, or blacks. @end table