SubtitleEdit/subtitleedit · error · Exception

{e.Message}

Error message

{e.Message}

What it means

Thrown by DCinemaSmpte2007.ValidationCallBack, an XML schema validation event handler attached during ToText export. When the generated DCinema XML fails validation against SMPTE-428-7-2007-DCST.xsd, the validator raises a ValidationEventArgs whose message is re-thrown as a bare Exception. This interrupts export and surfaces the schema violation.

Source

Thrown at src/libse/SubtitleFormats/DCinemaSmpte2007.cs:591

                    xmld.LoadXml(result);
                    using (var xr = XmlReader.Create(zip))
                    {
                        xmld.Schemas.Add(null, xr);
                        xmld.Validate(ValidationCallBack);
                    }
                }
                catch (Exception exception)
                {
                    Errors = "Error validating xml via SMPTE-428-7-2007-DCST.xsd: " + exception.Message;
                }
            }

            return DCinemaSmpte2010.FixDcsTextSameLine(result);
        }

        private void ValidationCallBack(object sender, ValidationEventArgs e)
        {
            throw new Exception(e.Message);
        }

        public override void LoadSubtitle(Subtitle subtitle, List<string> lines, string fileName)
        {
            _errorCount = 0;
            var sb = new StringBuilder();
            lines.ForEach(line => sb.AppendLine(line));
            var xml = new XmlDocument { XmlResolver = null };
            xml.LoadXml(sb.ToString().Replace("<dcst:", "<").Replace("</dcst:", "</").Replace("xmlns=\"http://www.smpte-ra.org/schemas/428-7/2007/DCST\"", string.Empty)); // tags might be prefixed with namespace (or not)... so we just remove them
            var ss = Configuration.Settings.SubtitleSettings;
            try
            {
                ss.InitializeDCinemaSettings(true);
                XmlNode node = xml.DocumentElement.SelectSingleNode("Id");
                if (node != null)
                {
                    ss.CurrentDCinemaSubtitleId = node.InnerText;
                }

View on GitHub (pinned to 17a9f07487)

Solutions

  1. Read the embedded e.Message — it identifies the exact schema rule violated and the offending element/attribute.
  2. Fix the subtitle data (UUIDs, font ids, time codes) so it satisfies the rule.
  3. Verify all referenced FontIds exist in the <FontList> and required attributes (Size, Color) are present.
  4. Validate against the XSD manually with an external validator to iterate faster.
Defensive patterns

Strategy: try-catch

Validate before calling

// Validate DCinema XML against the XSD yourself to surface errors with detail
var schemas = new XmlSchemaSet();
schemas.Add(null, "SMPTE-428-7-2007-DCST.xsd");
var settings = new XmlReaderSettings { ValidationType = ValidationType.Schema, Schemas = schemas };
settings.ValidationEventHandler += (s, e) => { /* collect e.Message without throwing */ };
using var reader = XmlReader.Create(xmlPath, settings);
while (reader.Read()) { }

Try / catch

try
{
    var text = format.ToText(subtitle, title);
}
catch (Exception ex) when (ex.Message.Contains("validation"))
{
    // e.Message names the schema rule; fix the subtitle data accordingly
    logger.Error(ex, "DCinema 2007 validation failed");
}

Prevention

When it happens

Trigger: Exporting a subtitle to DCinema XML (Interop 2007) whose content violates the SMPTE 428-7 schema — e.g. a UUID in the wrong format, a Font element missing required attributes, a TimeCode or FontId that does not match the schema's pattern, or text exceeding the max length for a subtitle.

Common situations: Subtitles with unusual characters, missing required UUIDs, font references to undefined Font elements, or empty/mandatory fields. Most often the root cause is in the data fed to ToText, not the schema itself.

Related errors

AI-assisted analysis of SubtitleEdit/subtitleedit@17a9f07487 (2026-08-13). Data as JSON: /api/errors/49a73e991d4b3fa5. Report an issue: GitHub.