I'm also very interested in this. I'm also trying to slow down and speed up mp3s though I don't mind pitch shift. I wish there was just an easy way to change sample rate in MediaPlayer.
On Mar 7, 9:39 pm, "David R." <[email protected]> wrote: > In my continuing quest to slow down or speed up MP3s without altering > the pitch, I came across mpg123. I am now at the point where I can > compile and run using the libraries, and I get decoded MP3s. > (Hooray!) Unfortunately, I'm at about 0.45x real-time on a G1, which > isn't fast enough. One guy was able to get 20x real-time using libmad > (http://apistudios.com/hosted/marzec/badlogic/wordpress/?p=231) but > I'd prefer not to use that since mpg123 is LGPL while libmad is GPL. > > I'm led to believe that the main advantage of mpg123 is the amount of > code optimized by using assembly. In particular, I want to use the - > DOPT_ARM, but doing so gives the error: > > out/apps/decoder/android-1.5-arm/objs/decoder/mpg123/src/libmpg123/ > synth.o: In function `synth_1to1_arm': > sources/decoder/mpg123/src/libmpg123/synth.c:537: undefined reference > to `synth_1to1_arm_asm' > > This is my Android.mk file: > # > # Unless required by applicable law or agreed to in writing, software > # distributed under the License is distributed on an "AS IS" BASIS, > # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or > implied. > # See the License for the specific language governing permissions and > # limitations under the License. > # > LOCAL_PATH := $(call my-dir) > > include $(CLEAR_VARS) > > LOCAL_MODULE := decoder > LOCAL_ARM_MODE := arm > LOCAL_SRC_FILES := media_decoder.cpp mpg123/src/libmpg123/libmpg123.c > mpg123/src/libmpg123/frame.c mpg123/src/libmpg123/parse.c mpg123/src/ > libmpg123/id3.c mpg123/src/libmpg123/icy.c mpg123/src/libmpg123/ > icy2utf8.c mpg123/src/libmpg123/format.c mpg123/src/libmpg123/ > readers.c mpg123/src/libmpg123/layer1.c mpg123/src/libmpg123/layer2.c > mpg123/src/libmpg123/layer3.c mpg123/src/libmpg123/optimize.c mpg123/ > src/libmpg123/synth.c mpg123/src/libmpg123/equalizer.c mpg123/src/ > libmpg123/dct64.c mpg123/src/libmpg123/tabinit.c mpg123/src/libmpg123/ > synth_real.c mpg123/src/libmpg123/synth_s32.c mpg123/src/libmpg123/ > stringbuf.c mpg123/src/libmpg123/compat.c mpg123/src/libmpg123/ > synth_arm.S > LOCAL_CFLAGS := -DHAVE_CONFIG_H -DFPM_ARM -ffast-math -O3 -DOPT_ARM > -DNO_8BIT -DNO_NTOM -nostdlib -enable-int-quality -mandroid > > include $(BUILD_SHARED_LIBRARY) > > It compiles and runs fine if I change -DOPT_ARM to -DOPT_GENERIC and > remove mpg123/src/libmpg123/synth_arm.S > > How can I decode MP3s at least as fast as real time without > immediately playing them? Really I need to be significantly faster > than that, depending on how much I can optimize my slowdown code. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
