Add support for raw CDP (Caption Distribution Packet) files

Author: cfsmp3

src/lib_ccx/general_loop.c

@@ -567,6 +567,104 @@ static size_t process_raw_for_mcc(struct encoder_ctx *enc_ctx, struct lib_cc_dec
 }
 
 // Raw file process
+// Parse raw CDP (Caption Distribution Packet) data
+// Returns number of bytes processed
+static size_t process_raw_cdp(struct encoder_ctx *enc_ctx, struct lib_cc_decode *dec_ctx,
+			      struct cc_subtitle *sub, unsigned char *buffer, size_t len)
+{
+	size_t pos = 0;
+	int cdp_count = 0;
+
+	while (pos + 10 < len) // Minimum CDP size
+	{
+		// Check for CDP identifier
+		if (buffer[pos] != 0x96 || buffer[pos + 1] != 0x69)
+		{
+			pos++;
+			continue;
+		}
+
+		unsigned char cdp_length = buffer[pos + 2];
+		if (pos + cdp_length > len)
+			break; // Incomplete CDP packet
+
+		unsigned char framerate_byte = buffer[pos + 3];
+		int framerate_code = framerate_byte >> 4;
+
+		// Skip to find cc_data section (0x72)
+		size_t cdp_pos = pos + 4; // After identifier, length, framerate
+		int cc_count = 0;
+		unsigned char *cc_data = NULL;
+
+		// Skip header sequence counter (2 bytes)
+		cdp_pos += 2;
+
+		// Look for cc_data section (0x72) within CDP
+		while (cdp_pos < pos + cdp_length - 4)
+		{
+			if (buffer[cdp_pos] == 0x72) // cc_data section
+			{
+				cc_count = buffer[cdp_pos + 1] & 0x1F;
+				cc_data = buffer + cdp_pos + 2;
+				break;
+			}
+			else if (buffer[cdp_pos] == 0x71) // time code section
+			{
+				cdp_pos += 5; // Skip time code section
+			}
+			else if (buffer[cdp_pos] == 0x73) // service info section
+			{
+				break; // Past cc_data
+			}
+			else if (buffer[cdp_pos] == 0x74) // footer
+			{
+				break;
+			}
+			else
+			{
+				cdp_pos++;
+			}
+		}
+
+		if (cc_count > 0 && cc_data != NULL)
+		{
+			// Calculate PTS based on CDP frame count and frame rate
+			static const int fps_table[] = {0, 24, 24, 25, 30, 30, 50, 60, 60};
+			int fps = (framerate_code < 9) ? fps_table[framerate_code] : 30;
+			LLONG pts = (LLONG)cdp_count * 90000 / fps;
+
+			// Set timing if not already set
+			if (dec_ctx->timing->pts_set == 0)
+			{
+				dec_ctx->timing->min_pts = pts;
+				dec_ctx->timing->pts_set = 2;
+				dec_ctx->timing->sync_pts = pts;
+			}
+			set_current_pts(dec_ctx->timing, pts);
+			set_fts(dec_ctx->timing);
+
+#ifndef DISABLE_RUST
+			// Enable DTVCC decoder for CEA-708 captions
+			if (dec_ctx->dtvcc_rust)
+			{
+				int is_active = ccxr_dtvcc_is_active(dec_ctx->dtvcc_rust);
+				if (!is_active)
+				{
+					ccxr_dtvcc_set_active(dec_ctx->dtvcc_rust, 1);
+				}
+			}
+#endif
+			// Process cc_data triplets through process_cc_data for 708 support
+			process_cc_data(enc_ctx, dec_ctx, cc_data, cc_count, sub);
+			cdp_count++;
+		}
+
+		pos += cdp_length;
+	}
+
+	return pos;
+}
+
 int raw_loop(struct lib_ccx_ctx *ctx)
 {
 	LLONG ret;
@@ -577,6 +675,7 @@ int raw_loop(struct lib_ccx_ctx *ctx)
 	int caps = 0;
 	int is_dvdraw = 0;     // Flag to track if this is DVD raw format
 	int is_scc = 0;	       // Flag to track if this is SCC format
+	int is_cdp = 0;	       // Flag to track if this is raw CDP format
 	int is_mcc_output = 0; // Flag for MCC output format
 
 	dec_ctx = update_decoder_list(ctx);
@@ -622,7 +721,15 @@ int raw_loop(struct lib_ccx_ctx *ctx)
 			mprint("Detected SCC (Scenarist Closed Caption) format\n");
 		}
 
-		if (is_mcc_output && !is_dvdraw && !is_scc)
+		// Check if this is raw CDP format (starts with 0x9669)
+		if (!is_cdp && !is_scc && !is_dvdraw && data->len >= 2 &&
+		    data->buffer[0] == 0x96 && data->buffer[1] == 0x69)
+		{
+			is_cdp = 1;
+			mprint("Detected raw CDP (Caption Distribution Packet) format\n");
+		}
+
+		if (is_mcc_output && !is_dvdraw && !is_scc && !is_cdp)
 		{
 			// For MCC output, encode raw data directly without decoding
 			// This preserves the original CEA-608 byte pairs in CDP format
@@ -640,6 +747,13 @@ int raw_loop(struct lib_ccx_ctx *ctx)
 			// Use Rust SCC implementation - handles timing internally via SMPTE timecodes
 			ret = ccxr_process_scc(dec_ctx, dec_sub, data->buffer, (unsigned int)data->len, ccx_options.scc_framerate);
 		}
+		else if (is_cdp)
+		{
+			// Process raw CDP packets (e.g., from SDI VANC capture)
+			ret = process_raw_cdp(enc_ctx, dec_ctx, dec_sub, data->buffer, data->len);
+			if (ret > 0)
+				caps = 1;
+		}
 		else
 		{
 			ret = process_raw(dec_ctx, dec_sub, data->buffer, data->len);

src/rust/build.rs

@@ -103,14 +103,11 @@ fn main() {
             if std::path::Path::new(cellar_ffmpeg).exists() {
                 // Find the FFmpeg version directory
                 if let Ok(entries) = std::fs::read_dir(cellar_ffmpeg) {
-                    for entry in entries {
-                        if let Ok(entry) = entry {
-                            let include_path = entry.path().join("include");
-                            if include_path.exists() {
-                                builder =
-                                    builder.clang_arg(format!("-I{}", include_path.display()));
-                                break;
-                            }
+                    for entry in entries.flatten() {
+                        let include_path = entry.path().join("include");
+                        if include_path.exists() {
+                            builder = builder.clang_arg(format!("-I{}", include_path.display()));
+                            break;
                         }
                     }
                 }