From b18357326ca1522d7fb7f4276ddebfccc29ce72c Mon Sep 17 00:00:00 2001 From: Paul B Mahol Date: Mon, 19 Mar 2012 02:52:08 +0000 Subject: LucasArts SMUSH VIMA audio decoder Signed-off-by: Paul B Mahol --- libavcodec/vima.c | 236 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 236 insertions(+) create mode 100644 libavcodec/vima.c (limited to 'libavcodec/vima.c') diff --git a/libavcodec/vima.c b/libavcodec/vima.c new file mode 100644 index 0000000000..7c9a22bfe7 --- /dev/null +++ b/libavcodec/vima.c @@ -0,0 +1,236 @@ +/* + * LucasArt VIMA decoder + * Copyright (c) 2012 Paul B Mahol + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "libavutil/audioconvert.h" +#include "avcodec.h" +#include "get_bits.h" +#include "adpcm_data.h" + +typedef struct { + AVFrame frame; + uint16_t predict_table[5786 * 2]; +} VimaContext; + +static const uint8_t size_table[] = +{ + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 +}; + +static const int8_t index_table1[] = +{ + -1, 4, -1, 4 +}; + +static const int8_t index_table2[] = +{ + -1, -1, 2, 6, -1, -1, 2, 6 +}; + +static const int8_t index_table3[] = +{ + -1, -1, -1, -1, 1, 2, 4, 6, + -1, -1, -1, -1, 1, 2, 4, 6 +}; + +static const int8_t index_table4[] = +{ + -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 2, 2, 4, 5, 6, + -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 2, 2, 4, 5, 6 +}; + +static const int8_t index_table5[] = +{ + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 2, 2, 2, + 2, 4, 4, 4, 5, 5, 6, 6, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 2, 2, 2, + 2, 4, 4, 4, 5, 5, 6, 6 +}; + +static const int8_t index_table6[] = +{ + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 2, 2, 2, 2, 2, 2, + 2, 2, 4, 4, 4, 4, 4, 4, + 5, 5, 5, 5, 6, 6, 6, 6, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 2, 2, 2, 2, 2, 2, + 2, 2, 4, 4, 4, 4, 4, 4, + 5, 5, 5, 5, 6, 6, 6, 6 +}; + +static const int8_t* const step_index_tables[] = +{ + index_table1, index_table2, index_table3, + index_table4, index_table5, index_table6 +}; + +static av_cold int decode_init(AVCodecContext *avctx) +{ + VimaContext *vima = avctx->priv_data; + int start_pos; + + for (start_pos = 0; start_pos < 64; start_pos++) { + unsigned int dest_pos, table_pos; + + for (table_pos = 0, dest_pos = start_pos; + table_pos < FF_ARRAY_ELEMS(ff_adpcm_step_table); + table_pos++, dest_pos += 64) { + int put = 0, count, table_value; + + table_value = ff_adpcm_step_table[table_pos]; + for (count = 32; count != 0; count >>= 1) { + if (start_pos & count) + put += table_value; + table_value >>= 1; + } + vima->predict_table[dest_pos] = put; + } + } + + avcodec_get_frame_defaults(&vima->frame); + avctx->coded_frame = &vima->frame; + avctx->sample_fmt = AV_SAMPLE_FMT_S16; + + return 0; +} + +static int decode_frame(AVCodecContext *avctx, void *data, + int *got_frame_ptr, AVPacket *pkt) +{ + GetBitContext gb; + VimaContext *vima = avctx->priv_data; + int16_t pcm_data[2]; + uint32_t samples; + int8_t channel_hint[2]; + int ret, chan, channels = 1; + + init_get_bits(&gb, pkt->data, pkt->size * 8); + + if (pkt->size < 13) + return AVERROR_INVALIDDATA; + + samples = get_bits_long(&gb, 32); + if (samples == 0xffffffff) { + skip_bits_long(&gb, 32); + samples = get_bits_long(&gb, 32); + } + + if (samples > pkt->size * 2) + return AVERROR_INVALIDDATA; + + channel_hint[0] = get_sbits(&gb, 8); + if (channel_hint[0] & 0x80) { + channel_hint[0] = ~channel_hint[0]; + channels = 2; + } + avctx->channels = channels; + avctx->channel_layout = (channels == 2) ? AV_CH_LAYOUT_STEREO : + AV_CH_LAYOUT_MONO; + pcm_data[0] = get_sbits(&gb, 16); + if (channels > 1) { + channel_hint[1] = get_sbits(&gb, 8); + pcm_data[1] = get_sbits(&gb, 16); + } + + vima->frame.nb_samples = samples; + if ((ret = avctx->get_buffer(avctx, &vima->frame)) < 0) { + av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + return ret; + } + + for (chan = 0; chan < channels; chan++) { + uint16_t *dest = (uint16_t*)vima->frame.data[0] + chan; + int step_index = channel_hint[chan]; + int output = pcm_data[chan]; + int sample; + + for (sample = 0; sample < samples; sample++) { + int lookup_size, lookup, highbit, lowbits; + + step_index = av_clip(step_index, 0, 88); + lookup_size = size_table[step_index]; + lookup = get_bits(&gb, lookup_size); + highbit = 1 << (lookup_size - 1); + lowbits = highbit - 1; + + if (lookup & highbit) + lookup ^= highbit; + else + highbit = 0; + + if (lookup == lowbits) { + output = get_sbits(&gb, 16); + } else { + int predict_index, diff; + + predict_index = (lookup << (7 - lookup_size)) | (step_index << 6); + predict_index = av_clip(predict_index, 0, 5785); + diff = vima->predict_table[predict_index]; + if (lookup) + diff += ff_adpcm_step_table[step_index] >> (lookup_size - 1); + if (highbit) + diff = -diff; + + output = av_clip_int16(output + diff); + } + + *dest = output; + dest += channels; + + step_index += step_index_tables[lookup_size - 2][lookup]; + } + } + + *got_frame_ptr = 1; + *(AVFrame *)data = vima->frame; + + return pkt->size; +} + +AVCodec ff_vima_decoder = { + .name = "vima", + .type = AVMEDIA_TYPE_AUDIO, + .id = CODEC_ID_VIMA, + .priv_data_size = sizeof(VimaContext), + .init = decode_init, + .decode = decode_frame, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("LucasArts VIMA audio"), +}; -- cgit v1.2.3