Dump rejected ffmpeg options to console

CHANGELOG.md

@@ -1,4 +1,6 @@
 
+ * Add `FFmpegLogCallback.logRejectedOptions()` for debugging purposes ([pull #2301](https://github.com/bytedeco/javacv/pull/2301))
+
 ### November 16, 2024 version 1.5.11
  * Fix memory leak in `FFmpegFrameGrabber` when decoding from `InputStream` ([pull #2214](https://github.com/bytedeco/javacv/pull/2214))
  * Upgrade dependencies for OpenBLAS 0.3.28, OpenCV 4.10.0, FFmpeg 7.1, Leptonica 1.85.0, Tesseract 5.5.0

src/main/java/org/bytedeco/javacv/FFmpegFrameGrabber.java

@@ -989,6 +989,7 @@ public synchronized void startUnsafe(boolean findStreamInfo) throws Exception {
                 throw new Exception("avformat_open_input() error " + ret + ": Could not open input \"" + filename + "\". (Has setFormat() been called?)");
             }
         }
+        FFmpegLogCallback.logRejectedOptions(options, "avformat_open_input");
         av_dict_free(options);
 
         oc.max_delay(maxDelay);
@@ -1072,6 +1073,7 @@ public synchronized void startUnsafe(boolean findStreamInfo) throws Exception {
             if ((ret = avcodec_open2(video_c, codec, options)) < 0) {
                 throw new Exception("avcodec_open2() error " + ret + ": Could not open video codec.");
             }
+            FFmpegLogCallback.logRejectedOptions(options, "avcodec_open2");
             av_dict_free(options);
 
             // Hack to correct wrong frame rates that seem to be generated by some codecs
@@ -1123,6 +1125,7 @@ public synchronized void startUnsafe(boolean findStreamInfo) throws Exception {
             if ((ret = avcodec_open2(audio_c, codec, options)) < 0) {
                 throw new Exception("avcodec_open2() error " + ret + ": Could not open audio codec.");
             }
+            FFmpegLogCallback.logRejectedOptions(options, "avcodec_open2");
             av_dict_free(options);
 
             // Allocate audio samples frame

src/main/java/org/bytedeco/javacv/FFmpegFrameRecorder.java

@@ -798,6 +798,7 @@ public synchronized void startUnsafe() throws Exception {
                 av_dict_free(options);
                 throw new Exception("avcodec_open2() error " + ret + ": Could not open video codec.");
             }
+            FFmpegLogCallback.logRejectedOptions(options, "avcodec_open2");
             av_dict_free(options);
 
             video_outbuf = null;
@@ -879,6 +880,7 @@ public synchronized void startUnsafe() throws Exception {
                 av_dict_free(options);
                 throw new Exception("avcodec_open2() error " + ret + ": Could not open audio codec.");
             }
+            FFmpegLogCallback.logRejectedOptions(options, "avcodec_open2");
             av_dict_free(options);
 
             audio_outbuf_size = 256 * 1024;
@@ -962,6 +964,7 @@ public synchronized void startUnsafe() throws Exception {
                 av_dict_free(options);
                 throw new Exception(errorMsg);
             }
+            FFmpegLogCallback.logRejectedOptions(options, "avio_open2");
             oc.pb(pb);
         }
 
@@ -976,6 +979,7 @@ public synchronized void startUnsafe() throws Exception {
             av_dict_free(options);
             throw new Exception(errorMsg);
         }
+        FFmpegLogCallback.logRejectedOptions(options, "avformat_write_header");
         av_dict_free(options);
 
         if (av_log_get_level() >= AV_LOG_INFO) {

src/main/java/org/bytedeco/javacv/FFmpegLogCallback.java

@@ -61,6 +61,18 @@ public static void setLevel(int level) {
         av_log_set_level(level);
     }
 
+    /** Logs the given rejected options regarding the given command */
+    public static void logRejectedOptions(final AVDictionary options, final String command) {
+        if (getLevel() >= AV_LOG_INFO && av_dict_count(options) > 0) {
+            final StringBuilder sb = new StringBuilder(command + " rejected some options:");
+            AVDictionaryEntry e = null;
+            while ((e = av_dict_iterate(options, e)) != null) {
+                sb.append("\tOption: ").append(e.key().getString()).append(", value: ").append(e.value().getString());
+            }
+            logger.info(sb.toString());
+        }
+    }
+
     @Override public void call(int level, BytePointer msg) {
         switch (level) {
             case AV_LOG_PANIC: