ppy/osu · error · InvalidOperationException

Color specified in incorrect format (should be R,G,B or R,G,

Error message

Color specified in incorrect format (should be R,G,B or R,G,B,A): {pair.Value}

What it means

Thrown by LegacyDecoder.convertSettingStringToColor4 when a colour specification line doesn't split into exactly 3 or 4 comma-separated components. The expected format is 'R,G,B' or 'R,G,B,A'. Having fewer than 3 or more than 4 values triggers this before any parsing is attempted.

Source

Thrown at osu.Game/Beatmaps/Formats/LegacyDecoder.cs:109

                case Section.Colours:
                    HandleColours(output, line, false);
                    return;
            }
        }

        protected string StripComments(string line)
        {
            int index = line.AsSpan().IndexOf("//".AsSpan());
            if (index > 0)
                return line.Substring(0, index);

            return line;
        }

        private Color4 convertSettingStringToColor4(string[] split, bool allowAlpha, KeyValuePair<string, string> pair)
        {
            if (split.Length != 3 && split.Length != 4)
                throw new InvalidOperationException($@"Color specified in incorrect format (should be R,G,B or R,G,B,A): {pair.Value}");

            Color4 colour;

            try
            {
                byte alpha = allowAlpha && split.Length == 4 ? byte.Parse(split[3]) : (byte)255;
                colour = new Color4(byte.Parse(split[0]), byte.Parse(split[1]), byte.Parse(split[2]), alpha);
            }
            catch
            {
                throw new InvalidOperationException(@"Color must be specified with 8-bit integer components");
            }

            return colour;
        }

        protected void HandleColours<TModel>(TModel output, string line, bool allowAlpha)
        {

View on GitHub (pinned to d9c73e12ad)

Solutions

1. Inspect the colour line shown in the error message and ensure it has exactly 3 (R,G,B) or 4 (R,G,B,A) integer values.
2. Fix the .osu/.osb file's [Colours] section: e.g. change 'Combo1 : 255,0,0' (valid) instead of 'Combo1 : 255,0' (invalid).
3. Re-export the beatmap/skin from a working editor if the file is extensively corrupted.

Example fix

// before (.osu [Colours] section):
// Combo1 : 255,128

// after:
// Combo1 : 255,128,0

// Validate colour format before parsing
string[] split = pair.Value.Split(',');
if (split.Length != 3 && split.Length != 4)
    throw new InvalidOperationException($"Invalid colour format: expected 3 or 4 components, got {split.Length}");

try
{
    decoder.Decode(reader);
}
catch (InvalidOperationException ex) when (ex.Message.Contains("incorrect format"))
{
    Logger.Log($"Malformed colour line in beatmap: {ex.Message}", LoggingTarget.Database);
}

When it happens

Trigger: Decoding a .osu/.osb file where a colour line in [Colours] (or a ComboN colour) has the wrong number of comma-separated values — e.g. 'Combo1 : 255' (1 value), 'Combo1 : 255,0,0,0,0' (5 values), or an empty value field.

Common situations: Manual editing of a .osu file where a colour line is truncated or has extra values; a buggy skin/beatmap editor that writes malformed colour strings; a copy-paste error introducing extra commas.

Related errors

• Color must be specified with 8-bit integer components
• Beat length cannot be NaN in a timing control point
• Not a number
• Ruleset is not available locally.
• Unknown event type: {split[0]}

AI-assisted analysis of ppy/osu@d9c73e12ad (2026-08-13). Data as JSON: /api/errors/5546240d74041135. Report an issue: GitHub.