cea608tott: port to updated libcaption API

gst-plugin-closedcaption/src/cea608tott.rs

@@ -77,12 +77,12 @@ impl Cea608ToTt {
             }
         };
 
-        let pts = buffer.get_pts();
-        if pts.is_none() {
+        let buffer_pts = buffer.get_pts();
+        if buffer_pts.is_none() {
             gst_error!(CAT, obj: pad, "Require timestamped buffers");
             return Err(gst::FlowError::Error);
         }
-        let pts = (pts.unwrap() as f64) / 1_000_000_000.0;
+        let pts = (buffer_pts.unwrap() as f64) / 1_000_000_000.0;
 
         let data = buffer.map_readable().map_err(|_| {
             gst_error!(CAT, obj: pad, "Can't map buffer readable");
@@ -96,7 +96,7 @@ impl Cea608ToTt {
             return Ok(gst::FlowSuccess::Ok);
         }
 
-        match state
+        let previous_text = match state
             .caption_frame
             .decode((data[0] as u16) << 8 | data[1] as u16, pts)
         {
@@ -105,32 +105,34 @@ impl Cea608ToTt {
                 gst_error!(CAT, obj: pad, "Failed to decode closed caption packet");
                 return Ok(gst::FlowSuccess::Ok);
             }
-            Ok(Status::Ready) => {
-                gst_debug!(CAT, obj: pad, "Have ready closed caption packet");
+            Ok(Status::Clear) => {
+                gst_debug!(CAT, obj: pad, "Clearing previous closed caption packet");
+                state.previous_text.take()
             }
-        }
+            Ok(Status::Ready) => {
+                gst_debug!(CAT, obj: pad, "Have new closed caption packet");
+                let text = match state.caption_frame.to_text() {
+                    Ok(text) => text,
+                    Err(_) => {
+                        gst_error!(CAT, obj: pad, "Failed to convert caption frame to text");
+                        return Ok(gst::FlowSuccess::Ok);
+                    }
+                };
 
-        let text = match state.caption_frame.to_text() {
-            Ok(text) => text,
-            Err(_) => {
-                gst_error!(CAT, obj: pad, "Failed to convert caption frame to text");
-                return Ok(gst::FlowSuccess::Ok);
+                state.previous_text.replace((buffer_pts, text))
             }
         };
 
-        let timestamp =
-            gst::ClockTime::from((state.caption_frame.timestamp() * 1_000_000_000.0) as u64);
-
-        let previous_text = match state.previous_text.replace((timestamp, text)) {
+        let previous_text = match previous_text {
             Some(previous_text) => previous_text,
             None => {
-                gst_debug!(CAT, obj: pad, "Have no previous text yet");
+                gst_debug!(CAT, obj: pad, "Have no previous text");
                 return Ok(gst::FlowSuccess::Ok);
             }
         };
 
-        let duration = if timestamp > previous_text.0 {
-            timestamp - previous_text.0
+        let duration = if buffer_pts > previous_text.0 {
+            buffer_pts - previous_text.0
         } else {
             0.into()
         };
@@ -516,6 +518,7 @@ use std::mem;
 enum Status {
     Ok,
     Ready,
+    Clear,
 }
 
 #[derive(Copy, Clone, Debug)]
@@ -541,6 +544,7 @@ impl CaptionFrame {
             match res {
                 ffi::libcaption_stauts_t_LIBCAPTION_OK => Ok(Status::Ok),
                 ffi::libcaption_stauts_t_LIBCAPTION_READY => Ok(Status::Ready),
+                ffi::libcaption_stauts_t_LIBCAPTION_CLEAR => Ok(Status::Clear),
                 _ => Err(Error),
             }
         }
@@ -557,10 +561,6 @@ impl CaptionFrame {
             String::from_utf8(data).map_err(|_| Error)
         }
     }
-
-    fn timestamp(&self) -> f64 {
-        self.0.timestamp
-    }
 }
 
 impl Default for CaptionFrame {

gst-plugin-closedcaption/tests/cea608tott.rs

@@ -42,28 +42,26 @@ fn test_parse() {
     let buf = gst::Buffer::from_mut_slice(Vec::from(data));
     assert_eq!(h.push(buf), Ok(gst::FlowSuccess::Ok));
 
-    // Check the first 6 output buffers
-    let expected: [(gst::ClockTime, gst::ClockTime, &'static str); 6] = [
-        (0.into(), 33_366_666.into(), ""),
+    // Check the first 4 output buffers
+    let expected: [(gst::ClockTime, gst::ClockTime, &'static str); 4] = [
         (
-            33_366_666.into(),
-            15_048_366_667.into(),
+            15_048_366_666.into(),
+            3_236_566_667.into(),
             "From New York,\r\nthis is Democracy Now!",
         ),
-        (15_081_733_333.into(), 3_236_566_667.into(), ""),
         (
-            18_318_300_000.into(),
-            700_700_000.into(),
+            18_985_633_333.into(),
+            1_234_566_667.into(),
             "Yes, I’m supporting\r\nDonald Trump.",
         ),
         (
-            19_019_000_000.into(),
-            1_234_566_666.into(),
+            20_220_200_000.into(),
+            2_168_833_333.into(),
             "I’m doing so as enthusiastically\r\nas I can,",
         ),
         (
-            20_253_566_666.into(),
-            2_168_833_334.into(),
+            22_389_033_333.into(),
+            2_235_566_667.into(),
             "even the fact I think\r\nhe’s a terrible human being.",
         ),
     ];