Sur d’autres sites (10397)

• dnn_backend_native_layer_mathunary : add abs support

  25 mai 2020, par Ting Fu

  dnn_backend_native_layer_mathunary : add abs support
  more math unary operations will be added here
  It can be tested with the model file generated with below python scripy :
  import tensorflow as tf
  
  import numpy as np
  
  import imageio
  in_img = imageio.imread('input.jpeg')
  
  in_img = in_img.astype(np.float32)/255.0
  
  in_data = in_img[np.newaxis, :]
  x = tf.placeholder(tf.float32, shape=[1, None, None, 3], name='dnn_in')
  
  x1 = tf.subtract(x, 0.5)
  
  x2 = tf.abs(x1)
  
  y = tf.identity(x2, name='dnn_out')
  sess=tf.Session()
  
  sess.run(tf.global_variables_initializer())
  graph_def = tf.graph_util.convert_variables_to_constants(sess, sess.graph_def, ['dnn_out'])
  
  tf.train.write_graph(graph_def, '.', 'image_process.pb', as_text=False)
  print("image_process.pb generated, please use \
  
  path_to_ffmpeg/tools/python/convert.py to generate image_process.model\n")
  output = sess.run(y, feed_dict=x : in_data)
  
  imageio.imsave("out.jpg", np.squeeze(output))
  Signed-off-by : Ting Fu <ting.fu@intel.com>
  
  Signed-off-by : Guo, Yejun <yejun.guo@intel.com>
  

  • [DH] libavfilter/dnn/Makefile
  • [DH] libavfilter/dnn/dnn_backend_native.h
  • [DH] libavfilter/dnn/dnn_backend_native_layer_mathunary.c
  • [DH] libavfilter/dnn/dnn_backend_native_layer_mathunary.h
  • [DH] libavfilter/dnn/dnn_backend_native_layers.c
  • [DH] tools/python/convert_from_tensorflow.py
  • [DH] tools/python/convert_header.py

• Remove black bars from DV video using ffmpeg [closed]

  2 juillet 2020, par AustinMaxi1750

  I have copied all my Panasonic DV videos (PAL) from the 1990s to my PC as 'dv avi' using Windows movie maker in the original quality (approx 13GB per hour of video).

  


  At the time the recordings were made I set the Panasonic camera to 16:9. However searching various forums indicates it was an illusion of 16:9 and black bars were superimposed on the 4:3 picture to give a cinematic feel. I have read also that the DV pixels are not square.

  


  As a result all my 16:9 recordings have black bars at the top and bottom when viewed on a 16:9 monitor. The file properties are as follows :

  


  Frame width : 720
Frame height : 576

  


  Is there a code in ffmpeg to remove the black bars ?

  


  I attach an example of what I have :
image with black bars

  


  and an example of what I want to achieve :
image without black bars

  


  I also want to convert the format without loss of quality so I can watch the videos without the black bars on a modern smart TV. My TV cannot play back DV AVI.

  


• How to get a list of video devices with a particular VendorID and/or ProductID using FFmpeg (on Mac OS)

  26 mai 2020, par mcgregor94086

  The master task :

  



  I am writing software for a multiple USB camera array. The camera may be connected to a CPU that has other USB cameras builtin or attached. I need to capture one 1920x1080 JPG image from EACH of MY array's cameras into a directory of images - but I need to EXCLUDE any OTHER cameras when taking pictures.

  



  Right now I am trying to implement for MacOS, but in the future I will be implementing for Windows, Linux, iOS and Android.

  



  What is known :

  



  I know the VendorID, ProductID and UniqueID (reported by the MacOS USB system System Hardware Report) for each of the cameras in the camera array.

  



  UNIQUESKY_CAR_CAMERA #5:

  Model ID: UVC Camera VendorID_7119 ProductID_2825
  Unique ID:    0x143400001bcf0b09

UNIQUESKY_CAR_CAMERA #6:

  Model ID: UVC Camera VendorID_7119 ProductID_2825
  Unique ID:    0x143300001bcf0b09


  



  The problem code :

  



  I made the following call to FFmpeg

  



  ffmpeg -nostdin -hide_banner -an -sn -dn  -f avfoundation -list_devices true -I 1


  



  I received the following result in stderr :

  



      [AVFoundation indev @ 0x7fc870e21800] AVFoundation video devices:
    [AVFoundation indev @ 0x7fc870e21800] [0] FaceTime HD Camera (Built-in)
    [AVFoundation indev @ 0x7fc870e21800] [1] UNIQUESKY_CAR_CAMERA #5
    [AVFoundation indev @ 0x7fc870e21800] [2] UNIQUESKY_CAR_CAMERA #6
    [AVFoundation indev @ 0x7fc870e21800] [3] Capture screen 0
    [AVFoundation indev @ 0x7fc870e21800] [4] Capture screen 1
    [AVFoundation indev @ 0x7fc870e21800] AVFoundation audio devices:
    [AVFoundation indev @ 0x7fc870e21800] [0] MacBook Pro Microphone
    1: Input/output error


  



  Of these devices listed in the output, I happen to know (in this particular TEST CASE) that the cameras in my test array, are only these two :

  



  [1] UNIQUESKY_CAR_CAMERA #5
[2] UNIQUESKY_CAR_CAMERA #6


  



  With this knowledge, I can select the indices (1 2) that I need, and then use the following code to capture an image from each :

  



  for i in 1 2; 
do
    ffmpeg  -y -hide_banner  -f avfoundation  -r 15 -video_size 1920x1080 -i 1  -f image2 -qscale:v 1 -qmin 1 -qmax 1 -frames:v 1 img$i.jpg;
done



  



  Unfortunately, in production use (i.e. outside of this test case), I CAN NOT rely on cameras all identifying themselves with the same TEXT "name" prefix (e.g. "UNIQUESKY_CAR_CAMERA"), so I can't just use grep to select the ones I want.

  



  But I CAN be sure that I will know their VendorID, ProductID and UniqueIDs.

  



  So, IF I could get

  



  ffmpeg  -nostdin -hide_banner -an -sn -dn  -f avfoundation -list_devices true -I 1


  



  to also list the VendorID and ProductID, then I could grep for those values.

  



  Is this solution possible ? I can't find syntax in the documentation or examples for how to set such limits.

  



  ALTERNATIVELY : if I could specify to FFmpeg -list_devices to limit the output list to just those with my specified VendorID and ProductIDs then I could easily get the list of device indices I will need for the succeeding image extraction.

  



  Is this solution possible ? I can't find syntax in the documentation or examples for how to set such limits.

  



  Special Note :
  
The cameras I am using are all 1920x1080, and that resolution is necessary for my application. As has been noted by many Mac users on the web, other image capture programs (such as imagesnap) sometimes capture images at lower resolution (1024x720) than the cameras are capable of, and will not capture images at higher resolutions such as (1920x1080). For this reason, and because it is available on ALL the OS platforms of interest to us, I chose to use FFmpeg.