From 79d15fd4dbdd4b6e18f6bf62dba0668f8b177c16 Mon Sep 17 00:00:00 2001 From: Kostya Shishkov Date: Sat, 11 Mar 2006 04:26:55 +0000 Subject: [PATCH] 16-bit DPCM and stereo support for Sierra VMD Originally committed as revision 5147 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/vmdav.c | 121 +++++++++++++++++++-------------------------- 1 file changed, 50 insertions(+), 71 deletions(-) diff --git a/libavcodec/vmdav.c b/libavcodec/vmdav.c index 34685b676d..b850a09f9a 100644 --- a/libavcodec/vmdav.c +++ b/libavcodec/vmdav.c @@ -414,16 +414,28 @@ typedef struct VmdAudioContext { int channels; int bits; int block_align; - unsigned char steps8[16]; - unsigned short steps16[16]; - unsigned short steps128[256]; - short predictors[2]; + int predictors[2]; } VmdAudioContext; +static uint16_t vmdaudio_table[128] = { + 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080, + 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120, + 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0, + 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230, + 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280, + 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0, + 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320, + 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370, + 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0, + 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480, + 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700, + 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00, + 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000 +}; + static int vmdaudio_decode_init(AVCodecContext *avctx) { VmdAudioContext *s = (VmdAudioContext *)avctx->priv_data; - int i; s->avctx = avctx; s->channels = avctx->channels; @@ -433,53 +445,25 @@ static int vmdaudio_decode_init(AVCodecContext *avctx) av_log(s->avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, block align = %d, sample rate = %d\n", s->channels, s->bits, s->block_align, avctx->sample_rate); - /* set up the steps8 and steps16 tables */ - for (i = 0; i < 8; i++) { - if (i < 4) - s->steps8[i] = i; - else - s->steps8[i] = s->steps8[i - 1] + i - 1; - - if (i == 0) - s->steps16[i] = 0; - else if (i == 1) - s->steps16[i] = 4; - else if (i == 2) - s->steps16[i] = 16; - else - s->steps16[i] = 1 << (i + 4); - } - - /* set up the step128 table */ - s->steps128[0] = 0; - s->steps128[1] = 8; - for (i = 0x02; i <= 0x20; i++) - s->steps128[i] = (i - 1) << 4; - for (i = 0x21; i <= 0x60; i++) - s->steps128[i] = (i + 0x1F) << 3; - for (i = 0x61; i <= 0x70; i++) - s->steps128[i] = (i - 0x51) << 6; - for (i = 0x71; i <= 0x78; i++) - s->steps128[i] = (i - 0x69) << 8; - for (i = 0x79; i <= 0x7D; i++) - s->steps128[i] = (i - 0x75) << 10; - s->steps128[0x7E] = 0x3000; - s->steps128[0x7F] = 0x4000; - - /* set up the negative half of each table */ - for (i = 0; i < 8; i++) { - s->steps8[i + 8] = -s->steps8[i]; - s->steps16[i + 8] = -s->steps16[i]; - } - for (i = 0; i < 128; i++) - s->steps128[i + 128] = -s->steps128[i]; - return 0; } static void vmdaudio_decode_audio(VmdAudioContext *s, unsigned char *data, - uint8_t *buf, int ratio) { + uint8_t *buf, int stereo) +{ + int i; + int chan = 0; + int16_t *out = (int16_t*)data; + for(i = 0; i < s->block_align; i++) { + if(buf[i] & 0x80) + s->predictors[chan] -= vmdaudio_table[buf[i] & 0x7F]; + else + s->predictors[chan] += vmdaudio_table[buf[i]]; + s->predictors[chan] = clip(s->predictors[chan], -32768, 32767); + out[i] = s->predictors[chan]; + chan ^= stereo; + } } static int vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data, @@ -488,44 +472,39 @@ static int vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data, int bytes_decoded = 0; int i; - if (silence) - av_log(s->avctx, AV_LOG_INFO, "silent block!\n"); +// if (silence) +// av_log(s->avctx, AV_LOG_INFO, "silent block!\n"); if (s->channels == 2) { /* stereo handling */ - if ((s->block_align & 0x01) == 0) { - if (silence) - memset(data, 0, s->block_align * 2); - else - vmdaudio_decode_audio(s, data, buf, 1); + if (silence) { + memset(data, 0, s->block_align * 2); } else { - if (silence) - memset(data, 0, s->block_align * 2); - else + if (s->bits == 16) vmdaudio_decode_audio(s, data, buf, 1); + else + /* copy the data but convert it to signed */ + for (i = 0; i < s->block_align; i++) + data[i * 2 + 1] = buf[i] + 0x80; } } else { + bytes_decoded = s->block_align * 2; /* mono handling */ if (silence) { - if (s->bits == 16) { - memset(data, 0, s->block_align * 2); - bytes_decoded = s->block_align * 2; - } else { -// memset(data, 0x00, s->block_align); -// bytes_decoded = s->block_align; -memset(data, 0x00, s->block_align * 2); -bytes_decoded = s->block_align * 2; - } + memset(data, 0, s->block_align * 2); } else { - /* copy the data but convert it to signed */ - for (i = 0; i < s->block_align; i++) - data[i * 2 + 1] = buf[i] + 0x80; - bytes_decoded = s->block_align * 2; + if (s->bits == 16) { + vmdaudio_decode_audio(s, data, buf, 0); + } else { + /* copy the data but convert it to signed */ + for (i = 0; i < s->block_align; i++) + data[i * 2 + 1] = buf[i] + 0x80; + } } } - return bytes_decoded; + return s->block_align * 2; } static int vmdaudio_decode_frame(AVCodecContext *avctx,