.mp4 output via FFmpeg fails.

[ailgun]

Hello, I'm trying to use a code as below to create a .mp4 file (it's by someone else but I just wanted to try it out). It should create a mp4 file but after it creates a temp folder containing all the png frames and it gets deleted as expected after the process is finished - but it leaves no .mp4 file behind.

I also installed ffmpeg via pip install.

I wonder what I might be doing wrong?

Thanks!

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import scipy.misc import os   cols, rows = 10, 4 nf = 24  # num frames per transitions ni = 4   # num transitions   folder='temp' os.makedirs(folder) os.makedirs('%s/composite'%folder) print("generating frames for individual faces") for i in tqdm(range(cols)):     for j in range(rows):         idx = np.random.randint(n, size=ni)         idx = np.append(idx, idx[0])         f = 1         for k in range(ni):             xp1, xp2 = Xp[idx[k]], Xp[idx[k+1]]             Z = [[(1.0-r)*i1 + r*i2 for i1, i2 in zip(xp1, xp2)] for r in np.linspace(0,1,nf)]             Y = [ np.clip(pca.inverse_transform(z),0,255).reshape((w,h,3)) for z in Z ]             for y in Y:                 scipy.misc.imsave('%s/face%02d_%02d_frame%04d.png'%(folder,i,j,f), y.astype('uint8'))                 f+=1 offset = np.random.randint(nf*(ni-1), size=cols*rows) print("compositing all the faces into one video") for f in tqdm(range(nf*ni)):     img = Image.new('RGB',(w * cols, h * rows))     for i in range(cols):         for j in range(rows):             fidx = 1+(f + offset[i*rows+j])%(nf*ni)             im = Image.open('%s/face%02d_%02d_frame%04d.png'%(folder,i,j,fidx))             img.paste(im, (i*w, j*h))     img = img.resize((int(1.2*img.size[0]), int(1.2*img.size[1]))) #upscale just a bit     scipy.misc.imsave('temp/composite/frame%04d.png'%f, img) cmd = "ffmpeg -i %s/composite/frame%%04d.png -c:v libx264 -pix_fmt yuv420p composite.mp4"%folder print(cmd) os.system(cmd) os.system("rm -rf %s"%folder) print("done!")

[Ofnuts]

Given than it prints the command it shouldn't be hard to try the command yourself and see if it produces a result? You can even comment out the os.system("rm -rf %s"%folder) line so that the PNGs remain in the temp folder for your tests.

[ailgun]

Thanks for the reply, it actually works on simpler things which I do, I mean I can get .mp4 outputs. But no luck with this one.
I re-installed ffmpeg and x264 via pip again but no luck either.

I guess I'll have to compose a video from the still pngs by keeping the 'temp' and using a video software.

Best wishes.