Qt toBase64和Linux base64不同

Subj。爲什麼會這樣？我試過所有的Qt toBase64的標誌，但沒有任何改變。Qt toBase64和Linux base64不同

擊：

cat Invader_1.png | base64

輸出：

iVBORw0KGgoAAAANSUhEUgAAAQAAAAEACAYAAABccqhmAAAABHNCSVQICAgIfAhkiAAAAAlwSFlz AAALEwAACxMBAJqcGAAAA0JJREFUeJzt3MFt20AURdHnQIWoFLoSq5S4E7uSsBR24mxiIIsgSDIT cex3DjBLjT5J4ULcTAIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAACcY0vyNmFt9x27yhbPaKovZw8AnEcAoJgAQDEBgGICAMUEAIoJABQTACgm AFBMAKCYAEAxAYBiAgDFBACKCQAUEwAod jl7gIUcSZ4n7fV18PNHkpfhKdZyS3Id3GPPnGd0TNgD FMNP + IK1 + 51nvoc97styvAJAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAQDEBgGICAMUEAIoJABQT ACgmAFBMAACSbBk/sML6GGsLSfwDgGoCAMUEAIoJABQTACgmAFBMAKCYAEAxAYBiAgDFBACKCQAU EwAoJgBQTACgmABAscvZA0xyS3Id3GP08 + 9ekxyDe1yTPA1PspaV7sst44eCHEleBvdgkj3nnzIz 87SZbYHrcF9 + V/YJ13M6rwBQTACgmABAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAQDEBgGICAMUE AIoJABQTACj2cPL3b0m + nTwDnOkxJx4u4h8AFBMAKCYAUEwAoJgAQDEBgGICAMUEAIoJABQTACgm AFBMAKCYAEAxAYBiAgDFBACKXc4eYJLXJMfgHtckT8OT8BH4vSxiS/I2YW0LzWKtv7aM2xaa5Z95 BYBiAgDFBACKCQAUEwAoJgBQTACgmABAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAQDEBmO8xyYP1 X9bjXzwH/oAAQDEBgGICAMUEAIoJABQTACgmAFBMAKCYAEAxAYBiAgDFBACKCQAUEwAoJgBQTACg 2OXk7z + SPE/aZ8YeM2bZfqwVvGT83lyT3Ab3mGXP5/u9HBP2YCF7 krdF1jbherYFruN97ROuh594 BYBiAgDFBACKCQAUEwAoJgBQTACgmABAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHAn3wG6mDu8 W58tNgAAAABJRU5ErkJggg ==

的Qt：

QImage image; 
image.load("/home/undead/Pictures/1489180309_Invader_1.png"); 
image.save(&buffer, "PNG"); 
buffer.close(); 
bytes_array = bytes_array.toBase64();

輸出：

iVBORw0KGgoAAAANSUhEUgAAAQAAAAEACAYAAABccqhmAAAACXBIWXMAAAsTAAALEwEAmpwYAAADQklEQVR4nO3cwW3bQBRF0edAhagUuhKrlLgTu5KwFHbibGIgiyBIMhNx7HcOMEuNPknh QtxMAgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAJxjS_I2YW33HbvKFs9oqi9nDwCcRwCgmABAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAQDEBgGICAMUEAIoJABQTACh2OXuAhRxJnift9XXw80eSl-Ep1nJLch3cY8-cZ3RM2AN-ac_4iTX7nWe-hz3uy3K8AkAxAYBiAgDFBACKCQAUEwAoJgBQTACgmABAMQGAYgIAxQQAigkAFBMAKCYAUEwAAJJsGT-wwvoYawtJ_AOAagIAxQQAigkAFBMAKCYAUEwAoJgAQDEBgGICAMUEAIoJABQTACgmAFBMAKCYAECxy9kDTHJLch3cY_Tz716THIN7XJM8DU-ylpXuyy3jh4IcSV4G92CSPeefMjPztJltgetwX36_9gnXczqvAFBMAKCYAEAxAYBiAgDFBACKCQAUEwAoJgBQTACgmABAMQGAYgIAxQQAigkAFBMAKPZw8vdvSb6dPAOc6TEnHi7iHwAUEwAoJgBQTACgmABAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAQDEBgGICAMUEAIpdzh5gktckx-Ae1yRPw5PwEfi9LGJL8jZhbQvNYq2_tozbFprln3kFgGICAMUEAIoJABQTACgmAFBMAKCYAEAxAYBiAgDFBACKCQAUEwAoJgBQTACgmABAMQGY7zHJg_Vf1uNfPAf-gABAMQGAYgIAxQQAigkAFBMAKCYAUEwAoJgAQDEBgGICAMUEAIoJABQTACgmAFBMAKDY5eTvP5I8T9pnxh4zZtl-rBW8ZPzeXJPcBveYZc_n-70cE_ZgIXuSt0XWNuF6tgWu433tE66Hn3gFgGICAMUEAIoJABQTACgmAFBMAKCYAEAxAYBiAgDFBACKCQAUEwAoJgBQTACgmAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAcCffAbqYO7xbny02AAAAAElFTkSuQmCC

來源

2017-03-13 Maximus

怎麼樣'buffer'和'bytes_array'界定？ –

如果我沒有弄錯PNG有壓縮級別。當你在做'image.save（＆buffer，「PNG」）;'QImage可以保存在不同的級別。 – JustRufus

我們可以得到一些驗證，說明輸入是一點一點的嗎？ – MrEricSir

您正在比較2種不同的東西。

cat Invader_1.png | base64

輸出Invader_1.png的base64二進制內容。

雖然

QImage image; 
image.load("/home/undead/Pictures/1489180309_Invader_1.png"); 
image.save(&buffer, "PNG"); 
buffer.close(); 
bytes_array = bytes_array.toBase64();

轉換1489180309_Invader_1.png成像素圖像，然後返回到PNG，然後輸出新的PNG的BASE64二進制內容。

正如@JustRufus和@TobySpeight所述，可以使用不同的設置（例如壓縮級別）和/或導致不同二進制內容的元數據創建相同圖像的PNG。

如果要比較的東西，你應該可以解決你的Qt代碼只是讀取文件：

來源

2017-03-14 08:25:22

不僅壓縮，而且元數據（甚至元數據項的排序）在創建新PNG時可能會有所不同。 –

@TobySpeight謝謝，我已經用你的評論更新了答案。 –

Qt toBase64和Linux base64不同

回答

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