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--- ffmpeg [2014/02/11 02:54] – javapimp
+++ ffmpeg [2023/08/18 18:15] (current) – external edit 127.0.0.1
@@ Line 47: / Line 47: @@
 for /r %%a in (%src%) do (ffmpeg -i "%%a" "%%~na.avi")
+</code>
+====== Concatenate two mp4 files ======
+The videos need to have the same aspects to be joined without re-encoding (same size, bitrate, etc.)
+<code>
+ffmpeg -i first.mp4 -c copy -bsf h264_mp4toannexb first.ts
+ffmpeg -i second.mp4 -c copy -bsf h264_mp4toannexb second.ts
+ffmpeg -i "concat:first.ts|second.ts" -c copy -bsf aac_adtstoasc output.mp4
+</code>
+====== Decent Blu-Ray Compression ======
+  * Determine the size of the black bars on top and bottom and crop them.
+  * Play with the compression ''-crf'' value.
+    * Ranges from 0 (lossless) to 51 (terrible)
+    * 18-28 is usually pretty good. Default is 23.
+    * The smaller the number the better quality but bigger output file.
+  * Crop filter: ''-filter:v "crop=out_w:out_h:x:y"''
+    * ''out_w'' is the width of the output rectangle
+    * ''out_h'' is the height of the output rectangle
+    * ''x'' and ''y'' specify the top left corner of the output rectangle
+    * Handbrake can be used as an easy way to get these values
+<code>
+ffmpeg -i input.mkv -filter:v "crop=1920:800:0:140" -c:v libx264 -preset medium -crf 23 -c:a aac -b:a 384k -strict -2 output.mp4
 </code>