yading@10: /* yading@10: * LucasArts VIMA decoder yading@10: * Copyright (c) 2012 Paul B Mahol yading@10: * yading@10: * This file is part of FFmpeg. yading@10: * yading@10: * FFmpeg is free software; you can redistribute it and/or yading@10: * modify it under the terms of the GNU Lesser General Public yading@10: * License as published by the Free Software Foundation; either yading@10: * version 2.1 of the License, or (at your option) any later version. yading@10: * yading@10: * FFmpeg is distributed in the hope that it will be useful, yading@10: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@10: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@10: * Lesser General Public License for more details. yading@10: * yading@10: * You should have received a copy of the GNU Lesser General Public yading@10: * License along with FFmpeg; if not, write to the Free Software yading@10: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@10: */ yading@10: yading@10: #include "libavutil/channel_layout.h" yading@10: #include "avcodec.h" yading@10: #include "get_bits.h" yading@10: #include "internal.h" yading@10: #include "adpcm_data.h" yading@10: yading@10: typedef struct { yading@10: uint16_t predict_table[5786 * 2]; yading@10: } VimaContext; yading@10: yading@10: static const uint8_t size_table[] = yading@10: { yading@10: 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, yading@10: 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, yading@10: 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, yading@10: 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, yading@10: 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, yading@10: 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 yading@10: }; yading@10: yading@10: static const int8_t index_table1[] = yading@10: { yading@10: -1, 4, -1, 4 yading@10: }; yading@10: yading@10: static const int8_t index_table2[] = yading@10: { yading@10: -1, -1, 2, 6, -1, -1, 2, 6 yading@10: }; yading@10: yading@10: static const int8_t index_table3[] = yading@10: { yading@10: -1, -1, -1, -1, 1, 2, 4, 6, yading@10: -1, -1, -1, -1, 1, 2, 4, 6 yading@10: }; yading@10: yading@10: static const int8_t index_table4[] = yading@10: { yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: 1, 1, 1, 2, 2, 4, 5, 6, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: 1, 1, 1, 2, 2, 4, 5, 6 yading@10: }; yading@10: yading@10: static const int8_t index_table5[] = yading@10: { yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: 1, 1, 1, 1, 1, 2, 2, 2, yading@10: 2, 4, 4, 4, 5, 5, 6, 6, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: 1, 1, 1, 1, 1, 2, 2, 2, yading@10: 2, 4, 4, 4, 5, 5, 6, 6 yading@10: }; yading@10: yading@10: static const int8_t index_table6[] = yading@10: { yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: 1, 1, 1, 1, 1, 1, 1, 1, yading@10: 1, 1, 2, 2, 2, 2, 2, 2, yading@10: 2, 2, 4, 4, 4, 4, 4, 4, yading@10: 5, 5, 5, 5, 6, 6, 6, 6, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: -1, -1, -1, -1, -1, -1, -1, -1, yading@10: 1, 1, 1, 1, 1, 1, 1, 1, yading@10: 1, 1, 2, 2, 2, 2, 2, 2, yading@10: 2, 2, 4, 4, 4, 4, 4, 4, yading@10: 5, 5, 5, 5, 6, 6, 6, 6 yading@10: }; yading@10: yading@10: static const int8_t* const step_index_tables[] = yading@10: { yading@10: index_table1, index_table2, index_table3, yading@10: index_table4, index_table5, index_table6 yading@10: }; yading@10: yading@10: static av_cold int decode_init(AVCodecContext *avctx) yading@10: { yading@10: VimaContext *vima = avctx->priv_data; yading@10: int start_pos; yading@10: yading@10: for (start_pos = 0; start_pos < 64; start_pos++) { yading@10: unsigned int dest_pos, table_pos; yading@10: yading@10: for (table_pos = 0, dest_pos = start_pos; yading@10: table_pos < FF_ARRAY_ELEMS(ff_adpcm_step_table); yading@10: table_pos++, dest_pos += 64) { yading@10: int put = 0, count, table_value; yading@10: yading@10: table_value = ff_adpcm_step_table[table_pos]; yading@10: for (count = 32; count != 0; count >>= 1) { yading@10: if (start_pos & count) yading@10: put += table_value; yading@10: table_value >>= 1; yading@10: } yading@10: vima->predict_table[dest_pos] = put; yading@10: } yading@10: } yading@10: yading@10: avctx->sample_fmt = AV_SAMPLE_FMT_S16; yading@10: yading@10: return 0; yading@10: } yading@10: yading@10: static int decode_frame(AVCodecContext *avctx, void *data, yading@10: int *got_frame_ptr, AVPacket *pkt) yading@10: { yading@10: GetBitContext gb; yading@10: VimaContext *vima = avctx->priv_data; yading@10: AVFrame *frame = data; yading@10: int16_t pcm_data[2]; yading@10: uint32_t samples; yading@10: int8_t channel_hint[2]; yading@10: int ret, chan, channels = 1; yading@10: yading@10: if (pkt->size < 13) yading@10: return AVERROR_INVALIDDATA; yading@10: yading@10: if ((ret = init_get_bits8(&gb, pkt->data, pkt->size)) < 0) yading@10: return ret; yading@10: yading@10: samples = get_bits_long(&gb, 32); yading@10: if (samples == 0xffffffff) { yading@10: skip_bits_long(&gb, 32); yading@10: samples = get_bits_long(&gb, 32); yading@10: } yading@10: yading@10: if (samples > pkt->size * 2) yading@10: return AVERROR_INVALIDDATA; yading@10: yading@10: channel_hint[0] = get_sbits(&gb, 8); yading@10: if (channel_hint[0] & 0x80) { yading@10: channel_hint[0] = ~channel_hint[0]; yading@10: channels = 2; yading@10: } yading@10: avctx->channels = channels; yading@10: avctx->channel_layout = (channels == 2) ? AV_CH_LAYOUT_STEREO : yading@10: AV_CH_LAYOUT_MONO; yading@10: pcm_data[0] = get_sbits(&gb, 16); yading@10: if (channels > 1) { yading@10: channel_hint[1] = get_sbits(&gb, 8); yading@10: pcm_data[1] = get_sbits(&gb, 16); yading@10: } yading@10: yading@10: frame->nb_samples = samples; yading@10: if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) yading@10: return ret; yading@10: yading@10: for (chan = 0; chan < channels; chan++) { yading@10: uint16_t *dest = (uint16_t*)frame->data[0] + chan; yading@10: int step_index = channel_hint[chan]; yading@10: int output = pcm_data[chan]; yading@10: int sample; yading@10: yading@10: for (sample = 0; sample < samples; sample++) { yading@10: int lookup_size, lookup, highbit, lowbits; yading@10: yading@10: step_index = av_clip(step_index, 0, 88); yading@10: lookup_size = size_table[step_index]; yading@10: lookup = get_bits(&gb, lookup_size); yading@10: highbit = 1 << (lookup_size - 1); yading@10: lowbits = highbit - 1; yading@10: yading@10: if (lookup & highbit) yading@10: lookup ^= highbit; yading@10: else yading@10: highbit = 0; yading@10: yading@10: if (lookup == lowbits) { yading@10: output = get_sbits(&gb, 16); yading@10: } else { yading@10: int predict_index, diff; yading@10: yading@10: predict_index = (lookup << (7 - lookup_size)) | (step_index << 6); yading@10: predict_index = av_clip(predict_index, 0, 5785); yading@10: diff = vima->predict_table[predict_index]; yading@10: if (lookup) yading@10: diff += ff_adpcm_step_table[step_index] >> (lookup_size - 1); yading@10: if (highbit) yading@10: diff = -diff; yading@10: yading@10: output = av_clip_int16(output + diff); yading@10: } yading@10: yading@10: *dest = output; yading@10: dest += channels; yading@10: yading@10: step_index += step_index_tables[lookup_size - 2][lookup]; yading@10: } yading@10: } yading@10: yading@10: *got_frame_ptr = 1; yading@10: yading@10: return pkt->size; yading@10: } yading@10: yading@10: AVCodec ff_vima_decoder = { yading@10: .name = "vima", yading@10: .type = AVMEDIA_TYPE_AUDIO, yading@10: .id = AV_CODEC_ID_VIMA, yading@10: .priv_data_size = sizeof(VimaContext), yading@10: .init = decode_init, yading@10: .decode = decode_frame, yading@10: .capabilities = CODEC_CAP_DR1, yading@10: .long_name = NULL_IF_CONFIG_SMALL("LucasArts VIMA audio"), yading@10: };