Differences

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--- doc:appunti:linux:video:fix_smartphone_portrait_videos [2018/04/07 15:35] – [The ffmpeg Recipe] niccolo
+++ doc:appunti:linux:video:fix_smartphone_portrait_videos [2018/04/07 15:46] – [The Gradient Overlay Mask] niccolo
@@ Line 22: / Line 22: @@
 {{choose_crop_area.png?direct&280 |Choose the crop area}}
-We wrote a **Python script** to assist in step #1, which calculate all the required numbers just provinding two parameters: the **crop_aspect** and the **offset_y**.
+We wrote a **[[#the_python_script|Python script]]** to assist in step #1, which calculate all the required numbers just provinding two parameters: the **crop_aspect** and the **offset_y**.
 Adjust the **crop_aspect** from 0.0 (which selects a square) to 1.0 (which selects the full rectangle of the picture). Using a square-shaped crop area we will get the **highest zoom** level into the video, but we will cut-out  a greather part of the frames, above and below the cropped region.
@@ Line 36: / Line 36: @@
 ===== The Gradient Overlay Mask =====
-When the cropped image is placed above the background, it is quite annoying to see the **sharp edge** of the image. A better approach is to gradually fade the image at the right and at left edges. This requires to blend the image and the background using a **gradient mask**. We prepared the mask as a PNG image, using **convert** by the ImageMagick suite.
+When the cropped image is placed above the background, it is quite annoying to see the **sharp edge** of the image. A better approach is to gradually fade the image at the right and at left edges. This requires to blend the image and the background using a **gradient mask**. We prepared the mask as a **{{gradient_overlay_mask.png?linkonly|PNG image}}**, using **convert** from the ImageMagick suite.
 <code>
@@ Line 47: / Line 47: @@
 </code>
-{{gradient_overlay_mask.png?direct&150|Overlay Mask With Gradient}}
+NOTICE: It seems that [[https://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=33804|there is a bug]] in ImageMagick **gradient:bounding-box**, so we had to generate the mask in top-down mode and rotate it 90 degrees afterward.
 ===== The ffmpeg Recipe =====
@@ Line 74: / Line 73: @@
 ===== The Python Script =====
-The Python script **smartphonevideo_2landscape** will make the calculation to prepare the whole incantation: it will print on the standard output a **shell script** with the proper invokation of **convert** and **ffmpeg**. Use it in this way:
+The Python script **{{smartphonevideo_2landscape.txt|smartphonevideo_2landscape}}** will make the calculation to prepare the whole incantation: it will print on the standard output a **shell script** with the proper invokation of **convert** and **ffmpeg**. Use it in this way:
 <code>