1

I have a group of PNG images that serve as background overlays in an automated photo booth i.e. you have from back to front:

  • the background image,
  • the photo taken by the booth,
  • the PNG overlay which is usually a single object that partially covers or in some way "goes with" the photo to ad depth.

On some of the overlays, the transparency works perfectly, but on others there is either solid white or black instead of the alpha, which completely covers the other two layers.

The softwares documentation just states the overlays need to be PNG images with no further info. I have reached out to the software company but I do not expect to hear back for a few days and was hoping someone might be able to give me a clue as to what I might need to change.

I will also add that they all show the transparency correctly in pretty much every image editing, thumbnail or viewing program on my Ubuntu laptop. The photo booth where the issue arises has Windows 7 and I am not sure what libraries or viewers the software is actually using until I hear back from them.

Here is the output from identify -verbose on a PNG image that displays correctly:

  Format: PNG (Portable Network Graphics)
  Mime type: image/png
  Class: DirectClass
  Geometry: 640x480+0+0
  Units: Undefined
  Colorspace: sRGB
  Type: TrueColorAlpha
  Base type: Undefined
  Endianess: Undefined
  Depth: 8-bit
  Channel depth:
    red: 8-bit
    green: 8-bit
    blue: 8-bit
    alpha: 8-bit
  Channel statistics:
    Pixels: 307200
    Red:
      min: 0  (0)
      max: 255 (1)
      mean: 217.872 (0.854402)
      standard deviation: 70.2587 (0.275524)
      kurtosis: 2.21872
      skewness: -1.90895
      entropy: 0.503322
    Green:
      min: 0  (0)
      max: 255 (1)
      mean: 201.398 (0.789796)
      standard deviation: 77.1564 (0.302574)
      kurtosis: 0.0308413
      skewness: -1.21497
      entropy: 0.606074
    Blue:
      min: 0  (0)
      max: 255 (1)
      mean: 169.601 (0.665101)
      standard deviation: 101.379 (0.397567)
      kurtosis: -1.58002
      skewness: -0.503504
      entropy: 0.593343
    Alpha:
      min: 0  (0)
      max: 255 (1)
      mean: 95.6067 (0.374928)
      standard deviation: 122.084 (0.478762)
      kurtosis: -1.71292
      skewness: 0.520888
      entropy: 0.199834
  Image statistics:
    Overall:
      min: 0  (0)
      max: 255 (1)
      mean: 171.119 (0.671057)
      standard deviation: 92.7197 (0.363607)
      kurtosis: -1.32843
      skewness: -0.691616
      entropy: 0.475643
  Alpha: srgba(255,255,255,0)   #FFFFFF00
  Rendering intent: Perceptual
  Gamma: 0.454545
  Chromaticity:
    red primary: (0.64,0.33)
    green primary: (0.3,0.6)
    blue primary: (0.15,0.06)
    white point: (0.3127,0.329)
  Background color: white
  Border color: srgba(223,223,223,1)
  Matte color: grey74
  Transparent color: none
  Interlace: None
  Intensity: Undefined
  Compose: Over
  Page geometry: 640x480+0+0
  Dispose: Undefined
  Iterations: 0
  Compression: Zip
  Orientation: Undefined
  Properties:
    date:create: 2021-01-23T17:41:03-06:00
    date:modify: 2021-01-23T17:41:02-06:00
    png:IHDR.bit-depth-orig: 8
    png:IHDR.bit_depth: 8
    png:IHDR.color-type-orig: 6
    png:IHDR.color_type: 6 (RGBA)
    png:IHDR.interlace_method: 0 (Not interlaced)
    png:IHDR.width,height: 640, 480
    png:sRGB: intent=0 (Perceptual Intent)
    signature: <REMOVED>
  Artifacts:
    filename: <REMOVED>.png
    verbose: true
  Tainted: False
  Filesize: 273962B
  Number pixels: 307200
  Pixels per second: 30.72MB
  User time: 0.000u
  Elapsed time: 0:01.010
  Version: ImageMagick 6.9.10-23 Q16 x86_64 20190101 https://imagemagick.org

Here is one that displays incorrectly:

  Format: PNG (Portable Network Graphics)
  Mime type: image/png
  Class: DirectClass
  Geometry: 640x480+0+0
  Units: Undefined
  Colorspace: sRGB
  Type: PaletteAlpha
  Base type: Undefined
  Endianess: Undefined
  Depth: 8-bit
  Channel depth:
    red: 8-bit
    green: 8-bit
    blue: 8-bit
    alpha: 8-bit
  Channel statistics:
    Pixels: 307200
    Red:
      min: 0  (0)
      max: 255 (1)
      mean: 219.832 (0.862087)
      standard deviation: 77.0846 (0.302293)
      kurtosis: 1.95444
      skewness: -1.90138
      entropy: 0.252264
    Green:
      min: 0  (0)
      max: 255 (1)
      mean: 219.059 (0.859055)
      standard deviation: 78.4113 (0.307495)
      kurtosis: 1.77701
      skewness: -1.86701
      entropy: 0.25144
    Blue:
      min: 0  (0)
      max: 255 (1)
      mean: 217.765 (0.85398)
      standard deviation: 80.8197 (0.31694)
      kurtosis: 1.56822
      skewness: -1.82729
      entropy: 0.250538
    Alpha:
      min: 0  (0)
      max: 255 (1)
      mean: 36.655 (0.143745)
      standard deviation: 89.2794 (0.350115)
      kurtosis: 2.13201
      skewness: 2.03117
      entropy: 0.121759
  Image statistics:
    Overall:
      min: 0  (0)
      max: 255 (1)
      mean: 173.328 (0.679717)
      standard deviation: 81.3988 (0.319211)
      kurtosis: -1.3788
      skewness: -0.733102
      entropy: 0.219
  Alpha: srgba(255,255,255,0)   #FFFFFF00
  Colors: 254
  Histogram:
     12423: (  0,  0,  0,  0) #00000000 none
       109: (  7,  8,  5,255) #070805FF srgba(7,8,5,1)
       397: ( 14, 14, 10,255) #0E0E0AFF srgba(14,14,10,1)
       728: ( 18, 18, 13,255) #12120DFF srgba(18,18,13,1)
       169: ( 19, 21, 21,255) #131515FF srgba(19,21,21,1)
       514: ( 22, 21, 16,255) #161510FF srgba(22,21,16,1)
       200: ( 22, 22, 17,255) #161611FF srgba(22,22,17,1)
       211: ( 22, 22, 18,255) #161612FF srgba(22,22,18,1)
       514: ( 25, 23, 17,255) #191711FF srgba(25,23,17,1)
       617: ( 25, 25, 20,255) #191914FF srgba(25,25,20,1)
       380: ( 28, 28, 23,255) #1C1C17FF srgba(28,28,23,1)
       228: ( 29, 29, 25,255) #1D1D19FF srgba(29,29,25,1)
       535: ( 30, 27, 19,255) #1E1B13FF srgba(30,27,19,1)
       429: ( 31, 29, 21,255) #1F1D15FF srgba(31,29,21,1)
        21: ( 31, 32, 24,247) #1F2018F7 srgba(31,32,24,0.968627)
       168: ( 32, 31, 23,255) #201F17FF srgba(32,31,23,1)
       203: ( 32, 32, 29,255) #20201DFF srgba(32,32,29,1)
       369: ( 33, 31, 23,255) #211F17FF srgba(33,31,23,1)
       161: ( 33, 31, 25,255) #211F19FF srgba(33,31,25,1)
       224: ( 35, 35, 33,255) #232321FF srgba(35,35,33,1)
       368: ( 36, 34, 26,255) #24221AFF srgba(36,34,26,1)
       494: ( 37, 32, 22,255) #252016FF srgba(37,32,22,1)
       482: ( 38, 35, 27,255) #26231BFF srgba(38,35,27,1)
       213: ( 39, 39, 38,255) #272726FF srgba(39,39,38,1)
       534: ( 41, 38, 30,255) #29261EFF srgba(41,38,30,1)
        11: ( 41, 40, 30,247) #29281EF7 srgba(41,40,30,0.968627)
       489: ( 42, 36, 25,255) #2A2419FF srgba(42,36,25,1)
       194: ( 43, 45, 45,255) #2B2D2DFF srgba(43,45,45,1)
       301: ( 44, 41, 31,255) #2C291FFF srgba(44,41,31,1)
       258: ( 44, 42, 35,255) #2C2A23FF srgba(44,42,35,1)
       193: ( 45, 42, 30,255) #2D2A1EFF srgba(45,42,30,1)
       179: ( 45, 43, 40,255) #2D2B28FF srgba(45,43,40,1)
       425: ( 46, 39, 28,255) #2E271CFF srgba(46,39,28,1)
       518: ( 48, 42, 31,255) #302A1FFF srgba(48,42,31,1)
       246: ( 48, 49, 49,255) #303131FF srgba(48,49,49,1)
       472: ( 49, 45, 34,255) #312D22FF srgba(49,45,34,1)
        20: ( 49, 48, 37,247) #313025F7 srgba(49,48,37,0.968627)
       175: ( 50, 46, 42,255) #322E2AFF srgba(50,46,42,1)
       263: ( 51, 47, 38,255) #332F26FF srgba(51,47,38,1)
       388: ( 52, 45, 34,255) #342D22FF srgba(52,45,34,1)
       288: ( 53, 47, 36,255) #352F24FF srgba(53,47,36,1)
       384: ( 53, 49, 39,255) #353127FF srgba(53,49,39,1)
       309: ( 53, 53, 53,255) #353535FF srgba(53,53,53,1)
       182: ( 54, 49, 45,255) #36312DFF srgba(54,49,45,1)
       324: ( 56, 47, 35,255) #382F23FF srgba(56,47,35,1)
       285: ( 56, 53, 42,255) #38352AFF srgba(56,53,42,1)
       155: ( 56, 54, 44,255) #38362CFF srgba(56,54,44,1)
       246: ( 56, 57, 58,255) #38393AFF srgba(56,57,58,1)
       475: ( 58, 50, 38,255) #3A3226FF srgba(58,50,38,1)
        12: ( 58, 55, 44,247) #3A372CF7 srgba(58,55,44,0.968627)
       271: ( 58, 55, 46,255) #3A372EFF srgba(58,55,46,1)
       230: ( 59, 51, 43,255) #3B332BFF srgba(59,51,43,1)
         6: ( 59, 54, 46,227) #3B362EE3 srgba(59,54,46,0.890196)
       393: ( 61, 53, 40,255) #3D3528FF srgba(61,53,40,1)
       395: ( 62, 55, 42,255) #3E372AFF srgba(62,55,42,1)
       249: ( 62, 63, 63,255) #3E3F3FFF srgba(62,63,63,1)
       131: ( 63, 53, 54,255) #3F3536FF srgba(63,53,54,1)
       441: ( 63, 57, 46,255) #3F392EFF srgba(63,57,46,1)
       246: ( 63, 60, 55,255) #3F3C37FF srgba(63,60,55,1)
       286: ( 64, 59, 49,255) #403B31FF srgba(64,59,49,1)
       140: ( 65, 67, 69,255) #414345FF srgba(65,67,69,1)
       346: ( 66, 56, 42,255) #42382AFF srgba(66,56,42,1)
       262: ( 66, 59, 48,255) #423B30FF srgba(66,59,48,1)
       205: ( 67, 60, 49,255) #433C31FF srgba(67,60,49,1)
         9: ( 67, 64, 56,191) #434038BF srgba(67,64,56,0.74902)
       221: ( 68, 62, 49,255) #443E31FF srgba(68,62,49,1)
       187: ( 68, 65, 55,255) #444137FF srgba(68,65,55,1)
       146: ( 69, 61, 63,255) #453D3FFF srgba(69,61,63,1)
       292: ( 69, 62, 51,255) #453E33FF srgba(69,62,51,1)
       174: ( 69, 67, 58,255) #45433AFF srgba(69,67,58,1)
       386: ( 70, 60, 45,255) #463C2DFF srgba(70,60,45,1)
       128: ( 70, 68, 66,255) #464442FF srgba(70,68,66,1)
       147: ( 70, 72, 74,255) #46484AFF srgba(70,72,74,1)
       113: ( 72, 63, 56,255) #483F38FF srgba(72,63,56,1)
       388: ( 72, 64, 51,255) #484033FF srgba(72,64,51,1)
        91: ( 72, 71, 66,255) #484742FF srgba(72,71,66,1)
       264: ( 73, 66, 54,255) #494236FF srgba(73,66,54,1)
       191: ( 75, 65, 55,255) #4B4137FF srgba(75,65,55,1)
        15: ( 75, 71, 61,154) #4B473D9A srgba(75,71,61,0.603922)
       120: ( 76, 64, 66,255) #4C4042FF srgba(76,64,66,1)
       362: ( 76, 66, 49,255) #4C4231FF srgba(76,66,49,1)
       313: ( 76, 70, 59,255) #4C463BFF srgba(76,70,59,1)
       131: ( 76, 73, 65,255) #4C4941FF srgba(76,73,65,1)
       471: ( 77, 69, 55,255) #4D4537FF srgba(77,69,55,1)
       257: ( 78, 71, 60,255) #4E473CFF srgba(78,71,60,1)
       163: ( 78, 76, 71,255) #4E4C47FF srgba(78,76,71,1)
       124: ( 78, 79, 82,255) #4E4F52FF srgba(78,79,82,1)
       126: ( 79, 70, 72,255) #4F4648FF srgba(79,70,72,1)
         9: ( 79, 74, 64,241) #4F4A40F1 srgba(79,74,64,0.945098)
       366: ( 80, 73, 61,255) #50493DFF srgba(80,73,61,1)
       229: ( 81, 75, 65,255) #514B41FF srgba(81,75,65,1)
         6: ( 81, 79, 82,237) #514F52ED srgba(81,79,82,0.929412)
       487: ( 82, 71, 54,255) #524736FF srgba(82,71,54,1)
        80: ( 82, 84, 87,255) #525457FF srgba(82,84,87,1)
       225: ( 84, 77, 64,255) #544D40FF srgba(84,77,64,1)
       227: ( 84, 80, 70,255) #545046FF srgba(84,80,70,1)
       234: ( 85, 78, 65,255) #554E41FF srgba(85,78,65,1)
       146: ( 86, 74, 75,255) #564A4BFF srgba(86,74,75,1)
       418: ( 86, 75, 59,255) #564B3BFF srgba(86,75,59,1)
        93: ( 86, 86, 81,255) #565651FF srgba(86,86,81,1)
       171: ( 87, 83, 75,255) #57534BFF srgba(87,83,75,1)
       258: ( 88, 80, 67,255) #585043FF srgba(88,80,67,1)
        19: ( 89, 84, 75, 86) #59544B56 srgba(89,84,75,0.337255)
       320: ( 90, 79, 61,255) #5A4F3DFF srgba(90,79,61,1)
       248: ( 90, 82, 70,255) #5A5246FF srgba(90,82,70,1)
        20: ( 90, 84, 74,121) #5A544A79 srgba(90,84,74,0.47451)
        97: ( 90, 88, 89,255) #5A5859FF srgba(90,88,89,1)
       327: ( 91, 82, 66,255) #5B5242FF srgba(91,82,66,1)
         6: ( 91, 83, 79,227) #5B534FE3 srgba(91,83,79,0.890196)
       156: ( 92, 80, 82,255) #5C5052FF srgba(92,80,82,1)
       386: ( 93, 86, 74,255) #5D564AFF srgba(93,86,74,1)
       215: ( 93, 89, 80,255) #5D5950FF srgba(93,89,80,1)
        94: ( 93, 93, 87,255) #5D5D57FF srgba(93,93,87,1)
        89: ( 93, 94, 96,255) #5D5E60FF srgba(93,94,96,1)
       406: ( 95, 85, 68,255) #5F5544FF srgba(95,85,68,1)
         9: ( 96, 90, 81,196) #605A51C4 srgba(96,90,81,0.768627)
       134: ( 98, 85, 87,255) #625557FF srgba(98,85,87,1)
       434: ( 98, 90, 76,255) #625A4CFF srgba(98,90,76,1)
        44: ( 99, 82, 59,255) #63523BFF srgba(99,82,59,1)
       323: ( 99, 88, 70,255) #635846FF srgba(99,88,70,1)
       267: ( 99, 93, 81,255) #635D51FF srgba(99,93,81,1)
        15: ( 99, 95, 89,172) #635F59AC srgba(99,95,89,0.67451)
         1: (100, 83, 66,236) #645342EC srgba(100,83,66,0.92549)
       240: (100, 96, 87,255) #646057FF srgba(100,96,87,1)
       104: (100, 98,101,255) #646265FF srgba(100,98,101,1)
        41: (102, 77, 77,255) #664D4DFF srgba(102,77,77,1)
       145: (103, 91, 93,255) #675B5DFF srgba(103,91,93,1)
       342: (103, 95, 79,255) #675F4FFF srgba(103,95,79,1)
       135: (103,100, 92,255) #67645CFF srgba(103,100,92,1)
       300: (104, 92, 73,255) #685C49FF srgba(104,92,73,1)
         6: (105,102, 93,236) #69665DEC srgba(105,102,93,0.92549)
        37: (105,109,115,255) #696D73FF srgba(105,109,115,1)
       274: (106, 98, 82,255) #6A6252FF srgba(106,98,82,1)
       118: (106,101, 93,255) #6A655DFF srgba(106,101,93,1)
       219: (107, 96, 78,255) #6B604EFF srgba(107,96,78,1)
       246: (107, 99, 86,255) #6B6356FF srgba(107,99,86,1)
       114: (108,103,106,255) #6C676AFF srgba(108,103,106,1)
       181: (108,104, 96,255) #6C6860FF srgba(108,104,96,1)
       147: (109, 96,100,255) #6D6064FF srgba(109,96,100,1)
       180: (109,102, 89,255) #6D6659FF srgba(109,102,89,1)
         7: (109,106,113,219) #6D6A71DB srgba(109,106,113,0.858824)
        38: (110, 86, 86,255) #6E5656FF srgba(110,86,86,1)
       153: (110,102, 87,255) #6E6657FF srgba(110,102,87,1)
       195: (111, 99, 81,255) #6F6351FF srgba(111,99,81,1)
       138: (111,108,101,255) #6F6C65FF srgba(111,108,101,1)
        65: (113, 98, 76,255) #71624CFF srgba(113,98,76,1)
       248: (113,103, 85,255) #716755FF srgba(113,103,85,1)
       302: (113,105, 91,255) #71695BFF srgba(113,105,91,1)
       136: (115,102,106,255) #73666AFF srgba(115,102,106,1)
       288: (115,108, 97,255) #736C61FF srgba(115,108,97,1)
        71: (116, 94, 95,255) #745E5FFF srgba(116,94,95,1)
       164: (116,109,111,255) #746D6FFF srgba(116,109,111,1)
       315: (117,107, 90,255) #756B5AFF srgba(117,107,90,1)
       229: (117,112,104,255) #757068FF srgba(117,112,104,1)
        43: (117,112,104, 36) #75706824 srgba(117,112,104,0.141176)
       116: (120,105, 84,255) #786954FF srgba(120,105,84,1)
       308: (120,111, 95,255) #786F5FFF srgba(120,111,95,1)
       123: (120,118,111,255) #78766FFF srgba(120,118,111,1)
       287: (122,114, 99,255) #7A7263FF srgba(122,114,99,1)
        93: (122,121,119,255) #7A7977FF srgba(122,121,119,1)
       170: (123,110, 90,255) #7B6E5AFF srgba(123,110,90,1)
       140: (123,111,116,255) #7B6F74FF srgba(123,111,116,1)
       293: (124,117,104,255) #7C7568FF srgba(124,117,104,1)
         4: (125,117,102,238) #7D7566EE srgba(125,117,102,0.933333)
        82: (126,103,105,255) #7E6769FF srgba(126,103,105,1)
       183: (126,114, 95,255) #7E725FFF srgba(126,114,95,1)
       212: (127,119,100,255) #7F7764FF srgba(127,119,100,1)
       296: (127,122,110,255) #7F7A6EFF srgba(127,122,110,1)
        18: (127,122,115,146) #7F7A7392 srgba(127,122,115,0.572549)
        26: (128,122,113, 98) #807A7162 srgba(128,122,113,0.384314)
        17: (128,125,116,253) #807D74FD srgba(128,125,116,0.992157)
       110: (128,127,124,255) #807F7CFF srgba(128,127,124,1)
       111: (129,116,121,255) #817479FF srgba(129,116,121,1)
        27: (129,125,117,190) #817D75BE srgba(129,125,117,0.745098)
        37: (130,126,117, 63) #827E753F srgba(130,126,117,0.247059)
       221: (131,121,104,255) #837968FF srgba(131,121,104,1)
        92: (132,118, 96,255) #847660FF srgba(132,118,96,1)
       174: (133,125,108,255) #857D6CFF srgba(133,125,108,1)
        82: (134,120,126,255) #86787EFF srgba(134,120,126,1)
       243: (134,127,114,255) #867F72FF srgba(134,127,114,1)
        20: (134,129,121,225) #868179E1 srgba(134,129,121,0.882353)
        55: (135,113,114,255) #877172FF srgba(135,113,114,1)
       112: (135,132,125,255) #87847DFF srgba(135,132,125,1)
        93: (135,134,134,255) #878686FF srgba(135,134,134,1)
       149: (136,131,119,255) #888377FF srgba(136,131,119,1)
        82: (137,124,102,255) #897C66FF srgba(137,124,102,1)
       139: (140,129,110,255) #8C816EFF srgba(140,129,110,1)
       126: (141,139,137,255) #8D8B89FF srgba(141,139,137,1)
       148: (142,138,128,255) #8E8A80FF srgba(142,138,128,1)
       192: (143,135,120,255) #8F8778FF srgba(143,135,120,1)
        24: (143,139,134,153) #8F8B8699 srgba(143,139,134,0.6)
        62: (145,124,129,255) #917C81FF srgba(145,124,129,1)
        68: (145,145,146,255) #919192FF srgba(145,145,146,1)
       117: (147,144,135,255) #939087FF srgba(147,144,135,1)
        44: (148,126,101,255) #947E65FF srgba(148,126,101,1)
        26: (148,144,140,216) #94908CD8 srgba(148,144,140,0.847059)
       151: (150,141,125,255) #968D7DFF srgba(150,141,125,1)
        73: (151,135,115,255) #978773FF srgba(151,135,115,1)
        25: (151,147,142,121) #97938E79 srgba(151,147,142,0.47451)
       125: (152,149,142,255) #98958EFF srgba(152,149,142,1)
       103: (152,152,150,255) #989896FF srgba(152,152,150,1)
       105: (153,146,133,255) #999285FF srgba(153,146,133,1)
        49: (153,155,157,255) #999B9DFF srgba(153,155,157,1)
       100: (158,158,155,255) #9E9E9BFF srgba(158,158,155,1)
        64: (159,138,111,255) #9F8A6FFF srgba(159,138,111,1)
       102: (159,150,136,255) #9F9688FF srgba(159,150,136,1)
       169: (159,155,145,255) #9F9B91FF srgba(159,155,145,1)
       107: (163,162,160,255) #A3A2A0FF srgba(163,162,160,1)
        58: (163,164,165,255) #A3A4A5FF srgba(163,164,165,1)
        47: (164,146,121,254) #A49279FE srgba(164,146,121,0.996078)
       105: (164,161,153,255) #A4A199FF srgba(164,161,153,1)
        30: (167,166,164, 87) #A7A6A457 srgba(167,166,164,0.341176)
       124: (168,168,166,255) #A8A8A6FF srgba(168,168,166,1)
        21: (170,164,158,167) #AAA49EA7 srgba(170,164,158,0.654902)
        85: (170,167,158,255) #AAA79EFF srgba(170,167,158,1)
        85: (170,172,175,255) #AAACAFFF srgba(170,172,175,1)
        60: (171,154,128,255) #AB9A80FF srgba(171,154,128,1)
        23: (171,162,150,209) #ABA296D1 srgba(171,162,150,0.819608)
        77: (171,171,170,  8) #ABABAA08 srgba(171,171,170,0.0313725)
        41: (172,161,144,255) #ACA190FF srgba(172,161,144,1)
       124: (174,173,168,255) #AEADA8FF srgba(174,173,168,1)
        75: (175,178,181,255) #AFB2B5FF srgba(175,178,181,1)
       147: (178,178,175,255) #B2B2AFFF srgba(178,178,175,1)
        33: (179,178,177,126) #B3B2B17E srgba(179,178,177,0.494118)
        33: (180,171,153,255) #B4AB99FF srgba(180,171,153,1)
        54: (180,181,179, 17) #B4B5B311 srgba(180,181,179,0.0666667)
        64: (181,164,139,255) #B5A48BFF srgba(181,164,139,1)
       170: (182,182,181,255) #B6B6B5FF srgba(182,182,181,1)
        18: (183,181,175,197) #B7B5AFC5 srgba(183,181,175,0.772549)
       143: (184,186,188,255) #B8BABCFF srgba(184,186,188,1)
        29: (188,188,192,154) #BCBCC09A srgba(188,188,192,0.603922)
        59: (189,173,150,255) #BDAD96FF srgba(189,173,150,1)
       172: (189,190,190,255) #BDBEBEFF srgba(189,190,190,1)
        50: (190,181,160,255) #BEB5A0FF srgba(190,181,160,1)
       216: (192,194,196,255) #C0C2C4FF srgba(192,194,196,1)
       138: (196,197,199,255) #C4C5C7FF srgba(196,197,199,1)
       143: (196,199,202,255) #C4C7CAFF srgba(196,199,202,1)
        26: (197,193,175,255) #C5C1AFFF srgba(197,193,175,1)
       143: (198,201,205,255) #C6C9CDFF srgba(198,201,205,1)
        29: (198,202,206,220) #C6CACEDC srgba(198,202,206,0.862745)
       157: (200,204,207,255) #C8CCCFFF srgba(200,204,207,1)
        21: (201,189,163,255) #C9BDA3FF srgba(201,189,163,1)
       153: (204,207,210,255) #CCCFD2FF srgba(204,207,210,1)
        20: (204,208,212,172) #CCD0D4AC srgba(204,208,212,0.67451)
        83: (207,210,215,255) #CFD2D7FF srgba(207,210,215,1)
        24: (208,211,215,124) #D0D3D77C srgba(208,211,215,0.486275)
        21: (210,204,182,255) #D2CCB6FF srgba(210,204,182,1)
        61: (210,213,217, 28) #D2D5D91C srgba(210,213,217,0.109804)
        64: (211,214,216, 46) #D3D6D82E srgba(211,214,216,0.180392)
        29: (211,215,220, 91) #D3D7DC5B srgba(211,215,220,0.356863)
        36: (212,216,219,255) #D4D8DBFF srgba(212,216,219,1)
        45: (215,218,222, 69) #D7DADE45 srgba(215,218,222,0.270588)
         6: (242,247,242,255) #F2F7F2FF srgba(242,247,242,1)
    250080: (255,255,255,  0) #FFFFFF00 srgba(255,255,255,0)
  Rendering intent: Perceptual
  Gamma: 0.454545
  Chromaticity:
    red primary: (0.64,0.33)
    green primary: (0.3,0.6)
    blue primary: (0.15,0.06)
    white point: (0.3127,0.329)
  Background color: white
  Border color: srgba(223,223,223,1)
  Matte color: grey74
  Transparent color: none
  Interlace: None
  Intensity: Undefined
  Compose: Over
  Page geometry: 640x480+0+0
  Dispose: Undefined
  Iterations: 0
  Compression: Zip
  Orientation: Undefined
  Properties:
    date:create: 2021-01-23T17:41:06-06:00
    date:modify: 2021-01-23T17:41:06-06:00
    png:IHDR.bit-depth-orig: 8
    png:IHDR.bit_depth: 8
    png:IHDR.color-type-orig: 3
    png:IHDR.color_type: 3 (Indexed)
    png:IHDR.interlace_method: 0 (Not interlaced)
    png:IHDR.width,height: 640, 480
    png:PLTE.number_colors: 254
    png:sRGB: intent=0 (Perceptual Intent)
    png:tRNS: chunk was found
    signature: <REMOVED>
  Artifacts:
    filename: <REMOVED>
    verbose: true
  Tainted: False
  Filesize: 43765B
  Number pixels: 307200
  User time: 0.000u
  Elapsed time: 0:01.000
  Version: ImageMagick 6.9.10-23 Q16 x86_64 20190101 https://imagemagick.org

Any help would be appreciated.

2 Answers 2

3

Purely looking at the data.. it appears as though you have PNG8 and PNG32 images...

Simply examining the Properties:

Correct image...

 Properties:
    date:create: 2021-01-23T17:41:03-06:00
    date:modify: 2021-01-23T17:41:02-06:00
    png:IHDR.bit-depth-orig: 8
    png:IHDR.bit_depth: 8
    png:IHDR.color-type-orig: 6 ----------------------- color type variation
    png:IHDR.color_type: 6 (RGBA) --------------------- RGBA
    png:IHDR.interlace_method: 0 (Not interlaced)
    png:IHDR.width,height: 640, 480
    png:sRGB: intent=0 (Perceptual Intent)
    signature: <REMOVED>

vs incorrect image...

  Properties:
    date:create: 2021-01-23T17:41:06-06:00
    date:modify: 2021-01-23T17:41:06-06:00
    png:IHDR.bit-depth-orig: 8
    png:IHDR.bit_depth: 8
    png:IHDR.color-type-orig: 3 ---------------------- color type variation
    png:IHDR.color_type: 3 (Indexed) ----------------- Indexed
    png:IHDR.interlace_method: 0 (Not interlaced)
    png:IHDR.width,height: 640, 480
    png:PLTE.number_colors: 254
    png:sRGB: intent=0 (Perceptual Intent)
    png:tRNS: chunk was found ------------------------ chunk
    signature: <REMOVED>

The Indexed "color_type" would indicate a PNG8 file to me. And would account for transparency being mapped to a color (i.e. black or white) rather than alpha.

One can also look at the Type variation.... Type: TrueColorAlpha vs Type: PaletteAlpha

Chances are, you want to ensure all PNGs are PNG32 images and avoid PNG8 files.

0

You can fix this in Paint.Net

  • Load the PNG in Paint.net,
  • Click "Save As"
  • Overwrite the file with a Bit Depth of 24-bit.

The image preview will render against a white background.

Full credit goes to: https://forums.getpaint.net/topic/30381-removing-the-alpha-channel/

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