Rework Frame Length Calculation. Fixes issue with tllts mp3
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@34072 a95241bf-73f2-0310-859d-f6bbb57e9c96
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@@ -970,17 +970,21 @@ mp3Reader::IsValidStream(uint8 *buffer, int size)
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// that the length encoded in the header is correct,
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// that the length encoded in the header is correct,
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// and also that mpeg version and layer do not change
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// and also that mpeg version and layer do not change
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int length1 = GetFrameLength(buffer);
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int length1 = GetFrameLength(buffer);
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if (length1 < 0 || (length1 + 4) > size)
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if (length1 < 0 || (length1 + 4) > size)
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return false;
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return false;
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int version_index1 = (buffer[1] >> 3) & 0x03;
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int version_index1 = (buffer[1] >> 3) & 0x03;
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int layer_index1 = (buffer[1] >> 1) & 0x03;
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int layer_index1 = (buffer[1] >> 1) & 0x03;
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int length2 = GetFrameLength(buffer + length1);
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int length2 = GetFrameLength(buffer + length1);
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if (length2 < 0 || (length1 + length2 + 4) > size)
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if (length2 < 0 || (length1 + length2 + 4) > size)
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return false;
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return false;
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int version_index2 = (buffer[length1 + 1] >> 3) & 0x03;
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int version_index2 = (buffer[length1 + 1] >> 3) & 0x03;
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int layer_index2 = (buffer[length1 + 1] >> 1) & 0x03;
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int layer_index2 = (buffer[length1 + 1] >> 1) & 0x03;
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if (version_index1 != version_index2 || layer_index1 != layer_index1)
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if (version_index1 != version_index2 || layer_index1 != layer_index1)
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return false;
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return false;
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int length3 = GetFrameLength(buffer + length1 + length2);
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int length3 = GetFrameLength(buffer + length1 + length2);
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if (length3 < 0)
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if (length3 < 0)
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return false;
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return false;
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@@ -988,13 +992,16 @@ mp3Reader::IsValidStream(uint8 *buffer, int size)
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int layer_index3 = (buffer[length1 + length2 + 1] >> 1) & 0x03;
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int layer_index3 = (buffer[length1 + length2 + 1] >> 1) & 0x03;
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if (version_index2 != version_index3 || layer_index2 != layer_index3)
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if (version_index2 != version_index3 || layer_index2 != layer_index3)
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return false;
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return false;
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int length4 = GetFrameLength(buffer + length1 + length2 + length3);
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int length4 = GetFrameLength(buffer + length1 + length2 + length3);
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if (length4 < 0)
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if (length4 < 0)
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return false;
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return false;
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int version_index4 = (buffer[length1 + length2 + length3 + 1] >> 3) & 0x03;
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int version_index4 = (buffer[length1 + length2 + length3 + 1] >> 3) & 0x03;
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int layer_index4 = (buffer[length1 + length2 + length3 + 1] >> 1) & 0x03;
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int layer_index4 = (buffer[length1 + length2 + length3 + 1] >> 1) & 0x03;
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if (version_index3 != version_index4 || layer_index3 != layer_index4)
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if (version_index3 != version_index4 || layer_index3 != layer_index4)
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return false;
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return false;
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return true;
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return true;
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}
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}
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@@ -1002,19 +1009,23 @@ int
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mp3Reader::GetFrameLength(void *header)
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mp3Reader::GetFrameLength(void *header)
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{
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{
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uint8 *h = (uint8 *)header;
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uint8 *h = (uint8 *)header;
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bool lsf = false;
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if (h[0] != 0xff)
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if (h[0] != 0xff)
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return -1;
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return -1;
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if ((h[1] & 0xe0) != 0xe0)
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if ((h[1] & 0xe0) != 0xe0)
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return -1;
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return -1;
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int mpeg_version_index = (h[1] >> 3) & 0x03;
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int mpeg_version_index = (h[1] >> 3) & 0x03;
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int layer_index = (h[1] >> 1) & 0x03;
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int layer_index = (h[1] >> 1) & 0x03;
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int bitrate_index = (h[2] >> 4) & 0x0f;
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int bitrate_index = (h[2] >> 4) & 0x0f;
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int sampling_rate_index = (h[2] >> 2) & 0x03;
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int sampling_rate_index = (h[2] >> 2) & 0x03;
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int padding = (h[2] >> 1) & 0x01;
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int padding = (h[2] >> 1) & 0x01;
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/* not interested in the other bits */
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/* not interested in the other bits */
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lsf = (mpeg_version_index == 0) || (mpeg_version_index == 2);
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int bitrate = bit_rate_table[mpeg_version_index][layer_index][bitrate_index];
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int bitrate = bit_rate_table[mpeg_version_index][layer_index][bitrate_index];
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int framerate = frame_rate_table[mpeg_version_index][sampling_rate_index];
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int framerate = frame_rate_table[mpeg_version_index][sampling_rate_index];
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@@ -1022,17 +1033,22 @@ mp3Reader::GetFrameLength(void *header)
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return -1;
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return -1;
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int length;
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int length;
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if (layer_index == 3) // layer 1
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if (layer_index == 3) { // layer 1
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length = ((144 * 1000 * bitrate) / framerate) + (padding * 4);
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length = ((12 * 1000 * bitrate) / framerate + padding) * 4;
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else // layer 2 & 3
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} else if (layer_index == 2) { // layer 2
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length = ((144 * 1000 * bitrate) / framerate) + padding;
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length = ((144 * 1000 * bitrate) / framerate) + padding;
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} else if (lsf) { // layer 3 with lsf
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length = ((144 * 1000 * bitrate) / (framerate*2)) + padding;
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} else { // layer 3 without lsf
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length = ((144 * 1000 * bitrate) / framerate) + padding;
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}
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#if 0
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#if 0
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TRACE("%s %s, %s crc, bit rate %d, frame rate %d, padding %d, frame length %d\n",
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printf("%s %s, %s crc, bit rate %d, frame rate %d, padding %d, frame length %d lsf=%s\n",
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mpeg_version_index == 0 ? "mpeg 2.5" : (mpeg_version_index == 2 ? "mpeg 2" : "mpeg 1"),
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mpeg_version_index == 0 ? "mpeg 2.5" : (mpeg_version_index == 2 ? "mpeg 2" : "mpeg 1"),
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layer_index == 3 ? "layer 1" : (layer_index == 2 ? "layer 2" : "layer 3"),
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layer_index == 3 ? "layer 1" : (layer_index == 2 ? "layer 2" : "layer 3"),
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(h[1] & 0x01) ? "no" : "has",
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(h[1] & 0x01) ? "no" : "has",
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bitrate, framerate, padding, length);
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bitrate, framerate, padding, length, (lsf ? "true" : "false"));
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#endif
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#endif
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return length;
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return length;
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