[FIX]: Prevent CEA-708 decoder panic with -stdout on Windows

docs/CHANGES.TXT

@@ -1,5 +1,6 @@
 0.96 (2025-12-23)
 -----------------
+- Fix: Prevent CEA-708 decoder panic when using --stdout on Windows by safely handling writer output errors
 - New: Multi-page teletext extraction support (#665)
   - Extract multiple teletext pages simultaneously with separate output files
   - Use --tpage multiple times (e.g., --tpage 100 --tpage 200)

src/rust/src/decoder/service_decoder.rs

@@ -860,19 +860,27 @@ impl dtvcc_service_decoder {
 
     /// Print the contents of tv screen to the output file
     pub fn screen_print(&mut self, encoder: &mut encoder_ctx, timing: &mut ccx_common_timing_ctx) {
-        debug!("dtvcc_screen_print rust");
+        debug!("dtvcc::screen_print rust");
+
         self.cc_count += 1;
+
         unsafe {
-            let tv = &mut (*self.tv);
+            let tv = &mut *self.tv;
             tv.cc_count += 1;
+
             let sn = tv.service_number;
             let writer_ctx = &mut encoder.dtvcc_writers[(sn - 1) as usize];
+
             tv.update_time_hide(timing.get_visible_end(3));
-            let transcript_settings = if !encoder.transcript_settings.is_null() {
-                &*encoder.transcript_settings
-            } else {
-                &ccx_encoders_transcript_format::default()
+
+            let transcript_settings = match encoder.transcript_settings.as_ref() {
+                Some(ts) => ts,
+                None => {
+                    // No transcript settings => transcript output disabled
+                    return;
+                }
             };
+
             let mut writer = Writer::new(
                 &mut encoder.cea_708_counter,
                 encoder.subs_delay,
@@ -882,7 +890,10 @@ impl dtvcc_service_decoder {
                 transcript_settings,
                 encoder.no_bom,
             );
-            tv.writer_output(&mut writer).unwrap();
+
+            if let Err(e) = tv.writer_output(&mut writer) {
+                warn!("dtvcc::screen_print: writer_output failed: {}", e);
+            }
             tv.clear();
         }
     }
@@ -1190,18 +1201,17 @@ impl dtvcc_service_decoder {
     }
     /// Flush the decoder of any remaining subtitles
     pub fn flush(&self, encoder: &mut encoder_ctx) {
-        let transcript_settings = unsafe {
-            if !encoder.transcript_settings.is_null() {
-                &*encoder.transcript_settings
-            } else {
-                &ccx_encoders_transcript_format::default()
-            }
-        };
         unsafe {
-            let tv = &mut (*self.tv);
+            let tv = &mut *self.tv;
             let sn = tv.service_number;
             let writer_ctx = &mut encoder.dtvcc_writers[(sn - 1) as usize];
 
+            // If transcript output is disabled, do nothing
+            let transcript_settings = match encoder.transcript_settings.as_ref() {
+                Some(ts) => ts,
+                None => return,
+            };
+
             let mut writer = Writer::new(
                 &mut encoder.cea_708_counter,
                 encoder.subs_delay,
@@ -1211,6 +1221,7 @@ impl dtvcc_service_decoder {
                 transcript_settings,
                 encoder.no_bom,
             );
+
             writer.write_done();
         }
     }