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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1905 | serge | 1 | /* |
| 2 | monosynth.h: generic mono related synth functions |
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| 3 | |||
| 4 | copyright 1995-2008 by the mpg123 project - free software under the terms of the LGPL 2.1 |
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| 5 | see COPYING and AUTHORS files in distribution or http://mpg123.org |
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| 6 | initially written by Michael Hipp, generalized by Thomas Orgis |
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| 7 | |||
| 8 | This header is used multiple times to create different variants of these functions. |
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| 9 | See decode.c and synth.h . |
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| 10 | Hint: BLOCK, MONO_NAME, MONO2STEREO_NAME, SYNTH_NAME and SAMPLE_T do vary. |
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| 11 | |||
| 12 | Thomas looked closely at the decode_1to1, decode_2to1 and decode_4to1 contents, seeing that they are too similar to be separate files. |
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| 13 | This is what resulted... |
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| 14 | |||
| 15 | Reason to separate this from synth.h: |
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| 16 | There are decoders that have a special synth_1to1 but still can use these generic derivations for the mono stuff. |
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| 17 | It generally makes a good deal of sense to set SYNTH_NAME to opt_synth_1to1(fr) (or opt_synth_2to1(fr), etc.). |
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| 18 | */ |
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| 19 | |||
| 20 | /* Mono synth, wrapping over SYNTH_NAME */ |
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| 21 | int MONO_NAME(real *bandPtr, mpg123_handle *fr) |
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| 22 | { |
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| 23 | SAMPLE_T samples_tmp[BLOCK]; |
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| 24 | SAMPLE_T *tmp1 = samples_tmp; |
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| 25 | int i,ret; |
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| 26 | |||
| 27 | /* save buffer stuff, trick samples_tmp into there, decode, restore */ |
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| 28 | unsigned char *samples = fr->buffer.data; |
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| 29 | int pnt = fr->buffer.fill; |
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| 30 | fr->buffer.data = (unsigned char*) samples_tmp; |
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| 31 | fr->buffer.fill = 0; |
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| 32 | ret = SYNTH_NAME(bandPtr, 0, fr, 0); /* decode into samples_tmp */ |
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| 33 | fr->buffer.data = samples; /* restore original value */ |
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| 34 | |||
| 35 | /* now append samples from samples_tmp */ |
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| 36 | samples += pnt; /* just the next mem in frame buffer */ |
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| 37 | for(i=0;i<(BLOCK/2);i++) |
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| 38 | { |
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| 39 | *( (SAMPLE_T *)samples) = *tmp1; |
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| 40 | samples += sizeof(SAMPLE_T); |
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| 41 | tmp1 += 2; |
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| 42 | } |
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| 43 | fr->buffer.fill = pnt + (BLOCK/2)*sizeof(SAMPLE_T); |
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| 44 | |||
| 45 | return ret; |
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| 46 | } |
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| 47 | |||
| 48 | /* Mono to stereo synth, wrapping over SYNTH_NAME */ |
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| 49 | int MONO2STEREO_NAME(real *bandPtr, mpg123_handle *fr) |
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| 50 | { |
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| 51 | int i,ret; |
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| 52 | unsigned char *samples = fr->buffer.data; |
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| 53 | |||
| 54 | ret = SYNTH_NAME(bandPtr,0,fr,1); |
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| 55 | samples += fr->buffer.fill - BLOCK*sizeof(SAMPLE_T); |
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| 56 | |||
| 57 | for(i=0;i<(BLOCK/2);i++) |
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| 58 | { |
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| 59 | ((SAMPLE_T *)samples)[1] = ((SAMPLE_T *)samples)[0]; |
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| 60 | samples+=2*sizeof(SAMPLE_T); |
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| 61 | } |
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| 62 | |||
| 63 | return ret; |
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| 64 | } |