| /* |
| * Bink Audio decoder |
| * Copyright (c) 2007-2011 Peter Ross (pross@xvid.org) |
| * Copyright (c) 2009 Daniel Verkamp (daniel@drv.nu) |
| * |
| * 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 |
| */ |
| |
| /** |
| * @file |
| * Bink Audio decoder |
| * |
| * Technical details here: |
| * http://wiki.multimedia.cx/index.php?title=Bink_Audio |
| */ |
| |
| #include "libavutil/channel_layout.h" |
| #include "libavutil/intfloat.h" |
| |
| #define BITSTREAM_READER_LE |
| #include "avcodec.h" |
| #include "dct.h" |
| #include "decode.h" |
| #include "get_bits.h" |
| #include "internal.h" |
| #include "rdft.h" |
| #include "wma_freqs.h" |
| |
| #define MAX_CHANNELS 2 |
| #define BINK_BLOCK_MAX_SIZE (MAX_CHANNELS << 11) |
| |
| typedef struct BinkAudioContext { |
| GetBitContext gb; |
| int version_b; ///< Bink version 'b' |
| int first; |
| int channels; |
| int frame_len; ///< transform size (samples) |
| int overlap_len; ///< overlap size (samples) |
| int block_size; |
| int num_bands; |
| float root; |
| unsigned int bands[26]; |
| float previous[MAX_CHANNELS][BINK_BLOCK_MAX_SIZE / 16]; ///< coeffs from previous audio block |
| float quant_table[96]; |
| AVPacket *pkt; |
| union { |
| RDFTContext rdft; |
| DCTContext dct; |
| } trans; |
| } BinkAudioContext; |
| |
| |
| static av_cold int decode_init(AVCodecContext *avctx) |
| { |
| BinkAudioContext *s = avctx->priv_data; |
| int sample_rate = avctx->sample_rate; |
| int sample_rate_half; |
| int i; |
| int frame_len_bits; |
| |
| /* determine frame length */ |
| if (avctx->sample_rate < 22050) { |
| frame_len_bits = 9; |
| } else if (avctx->sample_rate < 44100) { |
| frame_len_bits = 10; |
| } else { |
| frame_len_bits = 11; |
| } |
| |
| if (avctx->channels < 1 || avctx->channels > MAX_CHANNELS) { |
| av_log(avctx, AV_LOG_ERROR, "invalid number of channels: %d\n", avctx->channels); |
| return AVERROR_INVALIDDATA; |
| } |
| avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO : |
| AV_CH_LAYOUT_STEREO; |
| |
| s->version_b = avctx->extradata_size >= 4 && avctx->extradata[3] == 'b'; |
| |
| if (avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) { |
| // audio is already interleaved for the RDFT format variant |
| avctx->sample_fmt = AV_SAMPLE_FMT_FLT; |
| if (sample_rate > INT_MAX / avctx->channels) |
| return AVERROR_INVALIDDATA; |
| sample_rate *= avctx->channels; |
| s->channels = 1; |
| if (!s->version_b) |
| frame_len_bits += av_log2(avctx->channels); |
| } else { |
| s->channels = avctx->channels; |
| avctx->sample_fmt = AV_SAMPLE_FMT_FLTP; |
| } |
| |
| s->frame_len = 1 << frame_len_bits; |
| s->overlap_len = s->frame_len / 16; |
| s->block_size = (s->frame_len - s->overlap_len) * s->channels; |
| sample_rate_half = (sample_rate + 1LL) / 2; |
| if (avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) |
| s->root = 2.0 / (sqrt(s->frame_len) * 32768.0); |
| else |
| s->root = s->frame_len / (sqrt(s->frame_len) * 32768.0); |
| for (i = 0; i < 96; i++) { |
| /* constant is result of 0.066399999/log10(M_E) */ |
| s->quant_table[i] = expf(i * 0.15289164787221953823f) * s->root; |
| } |
| |
| /* calculate number of bands */ |
| for (s->num_bands = 1; s->num_bands < 25; s->num_bands++) |
| if (sample_rate_half <= ff_wma_critical_freqs[s->num_bands - 1]) |
| break; |
| |
| /* populate bands data */ |
| s->bands[0] = 2; |
| for (i = 1; i < s->num_bands; i++) |
| s->bands[i] = (ff_wma_critical_freqs[i - 1] * s->frame_len / sample_rate_half) & ~1; |
| s->bands[s->num_bands] = s->frame_len; |
| |
| s->first = 1; |
| |
| if (CONFIG_BINKAUDIO_RDFT_DECODER && avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) |
| ff_rdft_init(&s->trans.rdft, frame_len_bits, DFT_C2R); |
| else if (CONFIG_BINKAUDIO_DCT_DECODER) |
| ff_dct_init(&s->trans.dct, frame_len_bits, DCT_III); |
| else |
| av_assert0(0); |
| |
| s->pkt = av_packet_alloc(); |
| if (!s->pkt) |
| return AVERROR(ENOMEM); |
| |
| return 0; |
| } |
| |
| static float get_float(GetBitContext *gb) |
| { |
| int power = get_bits(gb, 5); |
| float f = ldexpf(get_bits(gb, 23), power - 23); |
| if (get_bits1(gb)) |
| f = -f; |
| return f; |
| } |
| |
| static const uint8_t rle_length_tab[16] = { |
| 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 32, 64 |
| }; |
| |
| /** |
| * Decode Bink Audio block |
| * @param[out] out Output buffer (must contain s->block_size elements) |
| * @return 0 on success, negative error code on failure |
| */ |
| static int decode_block(BinkAudioContext *s, float **out, int use_dct) |
| { |
| int ch, i, j, k; |
| float q, quant[25]; |
| int width, coeff; |
| GetBitContext *gb = &s->gb; |
| |
| if (use_dct) |
| skip_bits(gb, 2); |
| |
| for (ch = 0; ch < s->channels; ch++) { |
| FFTSample *coeffs = out[ch]; |
| |
| if (s->version_b) { |
| if (get_bits_left(gb) < 64) |
| return AVERROR_INVALIDDATA; |
| coeffs[0] = av_int2float(get_bits_long(gb, 32)) * s->root; |
| coeffs[1] = av_int2float(get_bits_long(gb, 32)) * s->root; |
| } else { |
| if (get_bits_left(gb) < 58) |
| return AVERROR_INVALIDDATA; |
| coeffs[0] = get_float(gb) * s->root; |
| coeffs[1] = get_float(gb) * s->root; |
| } |
| |
| if (get_bits_left(gb) < s->num_bands * 8) |
| return AVERROR_INVALIDDATA; |
| for (i = 0; i < s->num_bands; i++) { |
| int value = get_bits(gb, 8); |
| quant[i] = s->quant_table[FFMIN(value, 95)]; |
| } |
| |
| k = 0; |
| q = quant[0]; |
| |
| // parse coefficients |
| i = 2; |
| while (i < s->frame_len) { |
| if (s->version_b) { |
| j = i + 16; |
| } else { |
| int v = get_bits1(gb); |
| if (v) { |
| v = get_bits(gb, 4); |
| j = i + rle_length_tab[v] * 8; |
| } else { |
| j = i + 8; |
| } |
| } |
| |
| j = FFMIN(j, s->frame_len); |
| |
| width = get_bits(gb, 4); |
| if (width == 0) { |
| memset(coeffs + i, 0, (j - i) * sizeof(*coeffs)); |
| i = j; |
| while (s->bands[k] < i) |
| q = quant[k++]; |
| } else { |
| while (i < j) { |
| if (s->bands[k] == i) |
| q = quant[k++]; |
| coeff = get_bits(gb, width); |
| if (coeff) { |
| int v; |
| v = get_bits1(gb); |
| if (v) |
| coeffs[i] = -q * coeff; |
| else |
| coeffs[i] = q * coeff; |
| } else { |
| coeffs[i] = 0.0f; |
| } |
| i++; |
| } |
| } |
| } |
| |
| if (CONFIG_BINKAUDIO_DCT_DECODER && use_dct) { |
| coeffs[0] /= 0.5; |
| s->trans.dct.dct_calc(&s->trans.dct, coeffs); |
| } |
| else if (CONFIG_BINKAUDIO_RDFT_DECODER) |
| s->trans.rdft.rdft_calc(&s->trans.rdft, coeffs); |
| } |
| |
| for (ch = 0; ch < s->channels; ch++) { |
| int j; |
| int count = s->overlap_len * s->channels; |
| if (!s->first) { |
| j = ch; |
| for (i = 0; i < s->overlap_len; i++, j += s->channels) |
| out[ch][i] = (s->previous[ch][i] * (count - j) + |
| out[ch][i] * j) / count; |
| } |
| memcpy(s->previous[ch], &out[ch][s->frame_len - s->overlap_len], |
| s->overlap_len * sizeof(*s->previous[ch])); |
| } |
| |
| s->first = 0; |
| |
| return 0; |
| } |
| |
| static av_cold int decode_end(AVCodecContext *avctx) |
| { |
| BinkAudioContext * s = avctx->priv_data; |
| if (CONFIG_BINKAUDIO_RDFT_DECODER && avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) |
| ff_rdft_end(&s->trans.rdft); |
| else if (CONFIG_BINKAUDIO_DCT_DECODER) |
| ff_dct_end(&s->trans.dct); |
| |
| av_packet_free(&s->pkt); |
| |
| return 0; |
| } |
| |
| static void get_bits_align32(GetBitContext *s) |
| { |
| int n = (-get_bits_count(s)) & 31; |
| if (n) skip_bits(s, n); |
| } |
| |
| static int binkaudio_receive_frame(AVCodecContext *avctx, AVFrame *frame) |
| { |
| BinkAudioContext *s = avctx->priv_data; |
| GetBitContext *gb = &s->gb; |
| int ret; |
| |
| if (!s->pkt->data) { |
| ret = ff_decode_get_packet(avctx, s->pkt); |
| if (ret < 0) |
| return ret; |
| |
| if (s->pkt->size < 4) { |
| av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| |
| ret = init_get_bits8(gb, s->pkt->data, s->pkt->size); |
| if (ret < 0) |
| goto fail; |
| |
| /* skip reported size */ |
| skip_bits_long(gb, 32); |
| } |
| |
| /* get output buffer */ |
| frame->nb_samples = s->frame_len; |
| if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
| return ret; |
| |
| if (decode_block(s, (float **)frame->extended_data, |
| avctx->codec->id == AV_CODEC_ID_BINKAUDIO_DCT)) { |
| av_log(avctx, AV_LOG_ERROR, "Incomplete packet\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| get_bits_align32(gb); |
| if (!get_bits_left(gb)) { |
| memset(gb, 0, sizeof(*gb)); |
| av_packet_unref(s->pkt); |
| } |
| |
| frame->nb_samples = s->block_size / avctx->channels; |
| |
| return 0; |
| fail: |
| av_packet_unref(s->pkt); |
| return ret; |
| } |
| |
| AVCodec ff_binkaudio_rdft_decoder = { |
| .name = "binkaudio_rdft", |
| .long_name = NULL_IF_CONFIG_SMALL("Bink Audio (RDFT)"), |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = AV_CODEC_ID_BINKAUDIO_RDFT, |
| .priv_data_size = sizeof(BinkAudioContext), |
| .init = decode_init, |
| .close = decode_end, |
| .receive_frame = binkaudio_receive_frame, |
| .capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_DR1, |
| }; |
| |
| AVCodec ff_binkaudio_dct_decoder = { |
| .name = "binkaudio_dct", |
| .long_name = NULL_IF_CONFIG_SMALL("Bink Audio (DCT)"), |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = AV_CODEC_ID_BINKAUDIO_DCT, |
| .priv_data_size = sizeof(BinkAudioContext), |
| .init = decode_init, |
| .close = decode_end, |
| .receive_frame = binkaudio_receive_frame, |
| .capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_DR1, |
| }; |
