我需要在mp4容器中读取并注入XMP元数据 .

我知道这可以在Android上使用“mp4parser”库，但我找不到iOS的等价物 .

对于读取部分，是否可以从相机胶卷读取每个素材以快速检查其360 XMP元数据？

为了写作，我正在尝试使用Adobe的XMP工具包 . 我在一个文件夹中有一个mp4视频，我想要注入360个元数据 .

注入metadatas后(我认为它有效)，我将视频导出到相机胶卷，但看起来视频转换为m4v并且它丢失了我写的每个元数据 . 它是预期的，还是我的代码错了？

这是代码：

MetadataManager.mm

#import "MetadataManager.h"

#define IOS_ENV 1

#include

#define TXMP_STRING_TYPE std::string

#define XMP_INCLUDE_XMPFILES 1

#include "XMP.incl_cpp"

#include "XMP.hpp"

#include

#include

using namespace std;

@implementation MetadataManager {

}

+ (void)write360Metadatas:(NSString *)filePath {

if (!SXMPMeta::Initialize())

exit(1);

if (!SXMPFiles::Initialize())

exit(1);

SXMPFiles myFile;

XMP_OptionBits opts = kXMPFiles_OpenForUpdate | kXMPFiles_OpenUseSmartHandler;

std::string status = "";

std::string filePathStd = std::string([filePath UTF8String]);

// First, try to open the file

bool ok = myFile.OpenFile(filePathStd, kXMP_UnknownFile, opts);

if( ! ok ){

status += "No smart handler available for " + filePathStd + "\n";

status += "Trying packet scanning.\n";

// Now try using packet scanning

opts = kXMPFiles_OpenForUpdate | kXMPFiles_OpenUsePacketScanning;

ok = myFile.OpenFile(filePathStd, kXMP_UnknownFile, opts);

}

if(ok){

SXMPMeta meta;

myFile.GetXMP( &meta );

displayPropertyValues(&meta);

injectMetadatas(&meta);

// Check we can put the XMP packet back into the file

if(myFile.CanPutXMP(meta))

{

// If so then update the file with the modified XMP

myFile.PutXMP(meta);

}

// Close the SXMPFile. This *must* be called. The XMP is not

// actually written and the disk file is not closed until this call is made.

myFile.CloseFile();

}

}

SXMPMeta createXMPFromRDF()

{

const char * rdf =

"

" xmlns:GSpherical='http://ns.google.com/videos/1.0/spherical/'>"

"true"

"true"

"Spherical Metadata Tool"

"equirectangular"

"

";

SXMPMeta meta;

// Loop over the rdf string and create the XMP object

// 10 characters at a time

int i;

for (i = 0; i < (long)strlen(rdf) - 10; i += 10 )

{

meta.ParseFromBuffer ( &rdf[i], 10, kXMP_ParseMoreBuffers );

}

// The last call has no kXMP_ParseMoreBuffers options, signifying

// this is the last input buffer

meta.ParseFromBuffer ( &rdf[i], (XMP_StringLen) strlen(rdf) - i );

return meta;

}

void injectMetadatas(SXMPMeta * meta)

{

// Add an item onto the dc:creator array

// Note the options used, kXMP_PropArrayIsOrdered, if the array does not exist it will be created

meta->AppendArrayItem(kXMP_NS_DC, "creator", kXMP_PropArrayIsOrdered, "Author Name", 0);

meta->AppendArrayItem(kXMP_NS_DC, "creator", kXMP_PropArrayIsOrdered, "Another Author Name", 0);

// Now update alt-text properties

meta->SetLocalizedText(kXMP_NS_DC, "title", "en", "en-US", "An English title");

meta->SetLocalizedText(kXMP_NS_DC, "title", "fr", "fr-FR", "Un titre Francais");

// Display the properties again to show changes

cout << "After update:" << endl;

displayPropertyValues(meta);

// Create a new XMP object from an RDF string

SXMPMeta rdfMeta = createXMPFromRDF();

// Append the newly created properties onto the original XMP object

// This will:

// a) Add ANY new TOP LEVEL properties in the source (rdfMeta) to the destination (meta)

// b) Replace any top level properties in the source with the matching properties from the destination

SXMPUtils::ApplyTemplate(meta, rdfMeta, kXMPTemplate_AddNewProperties | kXMPTemplate_ReplaceExistingProperties | kXMPTemplate_IncludeInternalProperties);

// Display the properties again to show changes

cout << "After Appending Properties:" << endl;

displayPropertyValues(meta);

}

void displayPropertyValues(SXMPMeta * meta)

{

// Read a simple property

string simpleValue; //Stores the value for the property

meta->GetProperty(kXMP_NS_XMP, "CreatorTool", &simpleValue, 0);

cout << "meta:CreatorTool = " << simpleValue << endl;

// Get the first and second element in the dc:creator array

string elementValue;

meta->GetArrayItem(kXMP_NS_DC, "creator", 1, &elementValue, 0);

if(elementValue != "")

{

cout << "dc:creator[1] = " << elementValue << endl;

meta->GetArrayItem(kXMP_NS_DC, "creator", 2, &elementValue, 0);

cout << "dc:creator[2] = " << elementValue << endl;

}

// Get the the entire dc:subject array

string propValue;

int arrSize = meta->CountArrayItems(kXMP_NS_DC, "subject");

for(int i = 1; i <= arrSize;i++)

{

meta->GetArrayItem(kXMP_NS_DC, "subject", i, &propValue, 0);

cout << "dc:subject[" << i << "] = " << propValue << endl;

}

// Get the dc:title for English and French

string itemValue;

string actualLang;

meta->GetLocalizedText(kXMP_NS_DC, "title", "en", "en-US", 0, &itemValue, 0);

cout << "dc:title in English = " << itemValue << endl;

meta->GetLocalizedText(kXMP_NS_DC, "title", "fr", "fr-FR", 0, &itemValue, 0);

cout << "dc:title in French = " << itemValue << endl;

// Get dc:MetadataDate

XMP_DateTime myDate;

if(meta->GetProperty_Date(kXMP_NS_XMP, "MetadataDate", &myDate, 0))

{

// Convert the date struct into a convenient string and display it

string myDateStr;

SXMPUtils::ConvertFromDate(myDate, &myDateStr);

cout << "meta:MetadataDate = " << myDateStr << endl;

}

cout << "----------------------------------------" << endl;

}

@end

任何帮助将不胜感激，谢谢 .