Beispiel #1
0
#include "nsAString.h"
#include "nsMimeTypes.h"
#include "mozilla/ModuleUtils.h"

#include "nsIClassInfoImpl.h"

// The minimum number of bytes that are needed to attempt to sniff an mp4 file.
static const unsigned MP4_MIN_BYTES_COUNT = 12;
// The maximum number of bytes to consider when attempting to sniff a file.
static const uint32_t MAX_BYTES_SNIFFED = 512;

NS_IMPL_ISUPPORTS1(nsMediaSniffer, nsIContentSniffer)

nsMediaSniffer::nsMediaSnifferEntry nsMediaSniffer::sSnifferEntries[] = {
  // The string OggS, followed by the null byte.
  PATTERN_ENTRY("\xFF\xFF\xFF\xFF\xFF", "OggS", APPLICATION_OGG),
  // The string RIFF, followed by four bytes, followed by the string WAVE
  PATTERN_ENTRY("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF", "RIFF\x00\x00\x00\x00WAVE", AUDIO_WAV),
  // WebM
  PATTERN_ENTRY("\xFF\xFF\xFF\xFF", "\x1A\x45\xDF\xA3", VIDEO_WEBM),
  // mp3 without ID3 tags.
  PATTERN_ENTRY("\xFF\xFB", "\xFF\xFA", AUDIO_MP3),
  // mp3 with ID3 tags, the string "ID3".
  PATTERN_ENTRY("\xFF\xFF\xFF", "ID3", AUDIO_MP3)
};

// This function implements mp4 sniffing algorithm, described at
// http://mimesniff.spec.whatwg.org/#signature-for-mp4
static bool MatchesMP4(const uint8_t* aData, const uint32_t aLength)
{
  if (aLength <= MP4_MIN_BYTES_COUNT) {
Beispiel #2
0
#include "nestegg/nestegg.h"
#endif

#include "nsIClassInfoImpl.h"
#include <algorithm>

// The minimum number of bytes that are needed to attempt to sniff an mp4 file.
static const unsigned MP4_MIN_BYTES_COUNT = 12;
// The maximum number of bytes to consider when attempting to sniff a file.
static const uint32_t MAX_BYTES_SNIFFED = 512;

NS_IMPL_ISUPPORTS1(nsMediaSniffer, nsIContentSniffer)

nsMediaSniffer::nsMediaSnifferEntry nsMediaSniffer::sSnifferEntries[] = {
  // The string OggS, followed by the null byte.
  PATTERN_ENTRY("\xFF\xFF\xFF\xFF\xFF", "OggS", APPLICATION_OGG),
  // The string RIFF, followed by four bytes, followed by the string WAVE
  PATTERN_ENTRY("\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF", "RIFF\x00\x00\x00\x00WAVE", AUDIO_WAV),
  // mp3 with ID3 tags, the string "ID3".
  PATTERN_ENTRY("\xFF\xFF\xFF", "ID3", AUDIO_MP3)
};

// This function implements mp4 sniffing algorithm, described at
// http://mimesniff.spec.whatwg.org/#signature-for-mp4
static bool MatchesMP4(const uint8_t* aData, const uint32_t aLength)
{
  if (aLength <= MP4_MIN_BYTES_COUNT) {
    return false;
  }
  // Conversion from big endian to host byte order.
  uint32_t boxSize = (uint32_t)(aData[3] | aData[2] << 8 | aData[1] << 16 | aData[0] << 24);