Merge "Speed up SniffMidi() by parsing the initial bytes of the header" into main (92949994) · Commits · e / os / android_frameworks_av

media/module/extractors/Android.bp

+18 −0

Original line number	Diff line number	Diff line
		@@ -73,3 +73,21 @@ cc_defaults {
		],
		},
		}

		aconfig_declarations {
		name: "android.media.extractor.flags-aconfig",
		package: "com.android.media.extractor.flags",
		container: "com.android.media",
		srcs: ["extractor.aconfig"],
		}

		cc_aconfig_library {
		name: "android.media.extractor.flags-aconfig-cc",
		aconfig_declarations: "android.media.extractor.flags-aconfig",
		host_supported: true,
		min_sdk_version: "29",
		apex_available: [
		"//apex_available:platform",
		"com.android.media",
		],
		}

media/module/extractors/extractor.aconfig

0 → 100644

+13 −0

Original line number	Diff line number	Diff line
		# Media Extractor flags.
		#
		# !!! Please add flags in alphabetical order. !!!
		package: "com.android.media.extractor.flags"
		container: "com.android.media"

		flag {
		name: "extractor_sniff_midi_optimizations"
		is_exported: true
		namespace: "media_extractor"
		description: "Enable SniffMidi optimizations."
		bug: "359920208"
		}

media/module/extractors/fuzzers/Android.bp

+7 −0

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@ package {
		// to get the below license kinds:
		// SPDX-license-identifier-Apache-2.0
		default_applicable_licenses: ["frameworks_av_license"],
		default_team: "trendy_team_android_media_solutions_playback",
		}

		cc_defaults {
		@@ -302,12 +303,18 @@ cc_fuzz {
		],

		static_libs: [
		"android.media.extractor.flags-aconfig-cc",
		"libaconfig_storage_read_api_cc",
		"libsonivox",
		"libmedia_midiiowrapper",
		"libmidiextractor",
		"libwatchdog",
		],

		shared_libs: [
		"server_configurable_flags",
		],

		dictionary: "midi_extractor_fuzzer.dict",

		host_supported: true,

media/module/extractors/midi/Android.bp

+3 −0

Original line number	Diff line number	Diff line
		@@ -32,6 +32,8 @@ cc_library {
		],

		static_libs: [
		"android.media.extractor.flags-aconfig-cc",
		"libaconfig_storage_read_api_cc",
		"libmedia_midiiowrapper",
		"libsonivoxwithoutjet",
		"libstagefright_foundation",
		@@ -40,6 +42,7 @@ cc_library {

		shared_libs: [
		"libbase",
		"server_configurable_flags",
		],

		host_supported: true,

media/module/extractors/midi/MidiExtractor.cpp

+131 −3

Original line number	Diff line number	Diff line
		@@ -20,6 +20,7 @@

		#include "MidiExtractor.h"

		#include <com_android_media_extractor_flags.h>
		#include <media/MidiIoWrapper.h>
		#include <media/stagefright/foundation/ADebug.h>
		#include <media/stagefright/MediaBufferGroup.h>
		@@ -323,10 +324,97 @@ media_status_t MidiExtractor::getMetaData(AMediaFormat *meta)
		return AMediaFormat_copy(meta, mFileMetadata);
		}

		// Sniffer
		static bool startsWith(const uint8_t buf, size_t size, const char pattern, size_t patternSize) {
		if (size < patternSize) {
		return false;
		}
		return (memcmp(buf, pattern, patternSize) == 0);
		}

		bool SniffMidi(CDataSource source, float confidence)
		{
		static bool isValidMThd(const uint8_t *buf, size_t size) {
		return startsWith(buf, size, "MThd", 4);
		}

		static bool isValidXmf(const uint8_t *buf, size_t size) {
		return startsWith(buf, size, "XMF_", 4);
		}

		static bool isValidImelody(const uint8_t *buf, size_t size) {
		return startsWith(buf, size, "BEGIN:IMELODY", 13);
		}

		static bool isValidRtttl(const uint8_t *buf, size_t size) {
		#define RTTTL_MAX_TITLE_LEN 32
		// rtttl starts with the following:
		// <title>:<type>=<value>
		//
		// Where:
		// - <title>: Up to 32 characters
		// - <type>: Single character indicating:
		// 'd' for duration
		// 'o' for octave
		// 'b' for beats per minute
		// - <value>: Corresponding value for the type
		if (size < 4) {
		return false;
		}
		for (size_t i = 0; i < RTTTL_MAX_TITLE_LEN && i < size; i++) {
		if (buf[i] == ':') {
		if (i < (size - 3) && buf[i + 2] == '=') {
		return true;
		}
		break;
		}
		}
		return false;
		}

		static bool isValidOta(const uint8_t *buf, size_t size) {
		#define OTA_RINGTONE 0x25
		#define OTA_SOUND 0x1d
		#define OTA_UNICODE 0x22

		// ota starts with the following:
		// <cmdLen><cmd1><cmd2>..<cmdN>
		//
		// Where:
		// - <cmdLen>: Single character command length
		// - <cmd1>: Single character (OTA_RINGTONE << 1)
		// - <cmd2>: Single character (OTA_SOUND << 1) or (OTA_UNICODE << 1)
		// and so on with last cmd being (0x1d << 1)

		if (size < 3) {
		return false;
		}

		uint8_t cmdLen = buf[0];
		if (cmdLen < 2) {
		return false;
		}

		if ((buf[1] >> 1) != OTA_RINGTONE) {
		return false;
		}
		cmdLen--;

		size_t i = 2;
		while(cmdLen && i < size) {
		switch(buf[i] >> 1) {
		case OTA_SOUND:
		return true;
		case OTA_UNICODE:
		break;
		default:
		return false;
		}
		cmdLen--;
		i++;
		}

		return false;
		}

		bool SniffMidiLegacy(CDataSource source, float confidence) {
		MidiEngine p(source, NULL, NULL);
		if (p.initCheck() == OK) {
		*confidence = 0.8;
		@@ -335,7 +423,47 @@ bool SniffMidi(CDataSource source, float confidence)
		}
		ALOGV("SniffMidi: no");
		return false;
		}

		bool SniffMidiEfficiently(CDataSource source, float confidence) {
		uint8_t header[128];
		int filled = source->readAt(source->handle, 0, header, sizeof(header));

		if (isValidMThd(header, filled)) {
		*confidence = 0.80;
		ALOGV("SniffMidi: yes, MThd");
		return true;
		}
		if (isValidXmf(header, filled)) {
		*confidence = 0.80;
		ALOGV("SniffMidi: yes, XMF_");
		return true;
		}
		if (isValidImelody(header, filled)) {
		*confidence = 0.80;
		ALOGV("SniffMidi: yes, imelody");
		return true;
		}
		if (isValidRtttl(header, filled)) {
		*confidence = 0.80;
		ALOGV("SniffMidi: yes, rtttl");
		return true;
		}
		if (isValidOta(header, filled)) {
		*confidence = 0.80;
		ALOGV("SniffMidi: yes, ota");
		return true;
		}
		ALOGV("SniffMidi: no");
		return false;
		}

		// Sniffer
		bool SniffMidi(CDataSource source, float confidence) {
		if(com::android::media::extractor::flags::extractor_sniff_midi_optimizations()) {
		return SniffMidiEfficiently(source, confidence);
		}
		return SniffMidiLegacy(source, confidence);
		}

		static const char *extensions[] = {