X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=synfig-core%2Ftags%2Fsynfig_0_61_05%2Fsynfig-core%2Fsrc%2Fmodules%2Fmod_libavcodec%2Flibavcodec%2Fdv.c;fp=synfig-core%2Ftags%2Fsynfig_0_61_05%2Fsynfig-core%2Fsrc%2Fmodules%2Fmod_libavcodec%2Flibavcodec%2Fdv.c;h=75fd26eea912890067ac195700c259a6c4e58f67;hb=299aecad571ca490ce017004a0d7e555d6df0520;hp=0000000000000000000000000000000000000000;hpb=42861dc634bef4059ca95e5292033315a0b9ce30;p=synfig.git diff --git a/synfig-core/tags/synfig_0_61_05/synfig-core/src/modules/mod_libavcodec/libavcodec/dv.c b/synfig-core/tags/synfig_0_61_05/synfig-core/src/modules/mod_libavcodec/libavcodec/dv.c new file mode 100644 index 0000000..75fd26e --- /dev/null +++ b/synfig-core/tags/synfig_0_61_05/synfig-core/src/modules/mod_libavcodec/libavcodec/dv.c @@ -0,0 +1,802 @@ +/* + * DV decoder + * Copyright (c) 2002 Fabrice Bellard. + * + * This library 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 of the License, or (at your option) any later version. + * + * This library 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 this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/** + * @file dv.c + * DV decoder. + */ +#include "avcodec.h" +#include "dsputil.h" +#include "mpegvideo.h" +#include "simple_idct.h" + +#define NTSC_FRAME_SIZE 120000 +#define PAL_FRAME_SIZE 144000 + +#define TEX_VLC_BITS 9 + +typedef struct DVVideoDecodeContext { + AVCodecContext *avctx; + GetBitContext gb; + VLC *vlc; + int sampling_411; /* 0 = 420, 1 = 411 */ + int width, height; + uint8_t *current_picture[3]; /* picture structure */ + AVFrame picture; + int linesize[3]; + DCTELEM block[5*6][64] __align8; + uint8_t dv_zigzag[2][64]; + uint8_t idct_permutation[64]; + /* XXX: move it to static storage ? */ + uint8_t dv_shift[2][22][64]; + void (*idct_put[2])(uint8_t *dest, int line_size, DCTELEM *block); +} DVVideoDecodeContext; + +#include "dvdata.h" + +static VLC dv_vlc; +/* XXX: also include quantization */ +static RL_VLC_ELEM *dv_rl_vlc[1]; + +static void dv_build_unquantize_tables(DVVideoDecodeContext *s) +{ + int i, q, j; + + /* NOTE: max left shift is 6 */ + for(q = 0; q < 22; q++) { + /* 88 unquant */ + for(i = 1; i < 64; i++) { + /* 88 table */ + j = s->idct_permutation[i]; + s->dv_shift[0][q][j] = + dv_quant_shifts[q][dv_88_areas[i]] + 1; + } + + /* 248 unquant */ + for(i = 1; i < 64; i++) { + /* 248 table */ + s->dv_shift[1][q][i] = + dv_quant_shifts[q][dv_248_areas[i]] + 1; + } + } +} + +static int dvvideo_decode_init(AVCodecContext *avctx) +{ + DVVideoDecodeContext *s = avctx->priv_data; + MpegEncContext s2; + static int done=0; + + if (!done) { + int i; + + done = 1; + + /* NOTE: as a trick, we use the fact the no codes are unused + to accelerate the parsing of partial codes */ + init_vlc(&dv_vlc, TEX_VLC_BITS, NB_DV_VLC, + dv_vlc_len, 1, 1, dv_vlc_bits, 2, 2); + + dv_rl_vlc[0] = av_malloc(dv_vlc.table_size * sizeof(RL_VLC_ELEM)); + for(i = 0; i < dv_vlc.table_size; i++){ + int code= dv_vlc.table[i][0]; + int len = dv_vlc.table[i][1]; + int level, run; + + if(len<0){ //more bits needed + run= 0; + level= code; + } else if (code == (NB_DV_VLC - 1)) { + /* EOB */ + run = 0; + level = 256; + } else { + run= dv_vlc_run[code] + 1; + level= dv_vlc_level[code]; + } + dv_rl_vlc[0][i].len = len; + dv_rl_vlc[0][i].level = level; + dv_rl_vlc[0][i].run = run; + } + } + + /* ugly way to get the idct & scantable */ + /* XXX: fix it */ + memset(&s2, 0, sizeof(MpegEncContext)); + s2.avctx = avctx; + dsputil_init(&s2.dsp, avctx); + if (DCT_common_init(&s2) < 0) + return -1; + + s->idct_put[0] = s2.dsp.idct_put; + memcpy(s->idct_permutation, s2.dsp.idct_permutation, 64); + memcpy(s->dv_zigzag[0], s2.intra_scantable.permutated, 64); + + /* XXX: use MMX also for idct248 */ + s->idct_put[1] = simple_idct248_put; + memcpy(s->dv_zigzag[1], dv_248_zigzag, 64); + + /* XXX: do it only for constant case */ + dv_build_unquantize_tables(s); + + return 0; +} + +//#define VLC_DEBUG + +typedef struct BlockInfo { + const uint8_t *shift_table; + const uint8_t *scan_table; + uint8_t pos; /* position in block */ + uint8_t eob_reached; /* true if EOB has been reached */ + uint8_t dct_mode; + uint8_t partial_bit_count; + uint16_t partial_bit_buffer; + int shift_offset; +} BlockInfo; + +/* block size in bits */ +static const uint16_t block_sizes[6] = { + 112, 112, 112, 112, 80, 80 +}; + +#ifndef ALT_BITSTREAM_READER +#warning only works with ALT_BITSTREAM_READER +#endif + +/* decode ac coefs */ +static void dv_decode_ac(DVVideoDecodeContext *s, + BlockInfo *mb, DCTELEM *block, int last_index) +{ + int last_re_index; + int shift_offset = mb->shift_offset; + const uint8_t *scan_table = mb->scan_table; + const uint8_t *shift_table = mb->shift_table; + int pos = mb->pos; + int level, pos1, sign, run; + int partial_bit_count; +#ifndef ALT_BITSTREAM_READER //FIXME + int re_index=0; + int re1_index=0; +#endif + OPEN_READER(re, &s->gb); + +#ifdef VLC_DEBUG + printf("start\n"); +#endif + + /* if we must parse a partial vlc, we do it here */ + partial_bit_count = mb->partial_bit_count; + if (partial_bit_count > 0) { + uint8_t buf[4]; + uint32_t v; + int l, l1; + GetBitContext gb1; + + /* build the dummy bit buffer */ + l = 16 - partial_bit_count; + UPDATE_CACHE(re, &s->gb); +#ifdef VLC_DEBUG + printf("show=%04x\n", SHOW_UBITS(re, &s->gb, 16)); +#endif + v = (mb->partial_bit_buffer << l) | SHOW_UBITS(re, &s->gb, l); + buf[0] = v >> 8; + buf[1] = v; +#ifdef VLC_DEBUG + printf("v=%04x cnt=%d %04x\n", + v, partial_bit_count, (mb->partial_bit_buffer << l)); +#endif + /* try to read the codeword */ + init_get_bits(&gb1, buf, 4*8); + { + OPEN_READER(re1, &gb1); + UPDATE_CACHE(re1, &gb1); + GET_RL_VLC(level, run, re1, &gb1, dv_rl_vlc[0], + TEX_VLC_BITS, 2); + l = re1_index; + CLOSE_READER(re1, &gb1); + } +#ifdef VLC_DEBUG + printf("****run=%d level=%d size=%d\n", run, level, l); +#endif + /* compute codeword length */ + l1 = (level != 256 && level != 0); + /* if too long, we cannot parse */ + l -= partial_bit_count; + if ((re_index + l + l1) > last_index) + return; + /* skip read bits */ + last_re_index = 0; /* avoid warning */ + re_index += l; + /* by definition, if we can read the vlc, all partial bits + will be read (otherwise we could have read the vlc before) */ + mb->partial_bit_count = 0; + UPDATE_CACHE(re, &s->gb); + goto handle_vlc; + } + + /* get the AC coefficients until last_index is reached */ + for(;;) { + UPDATE_CACHE(re, &s->gb); +#ifdef VLC_DEBUG + printf("%2d: bits=%04x index=%d\n", + pos, SHOW_UBITS(re, &s->gb, 16), re_index); +#endif + last_re_index = re_index; + GET_RL_VLC(level, run, re, &s->gb, dv_rl_vlc[0], + TEX_VLC_BITS, 2); + handle_vlc: +#ifdef VLC_DEBUG + printf("run=%d level=%d\n", run, level); +#endif + if (level == 256) { + if (re_index > last_index) { + cannot_read: + /* put position before read code */ + re_index = last_re_index; + mb->eob_reached = 0; + break; + } + /* EOB */ + mb->eob_reached = 1; + break; + } else if (level != 0) { + if ((re_index + 1) > last_index) + goto cannot_read; + sign = SHOW_SBITS(re, &s->gb, 1); + level = (level ^ sign) - sign; + LAST_SKIP_BITS(re, &s->gb, 1); + pos += run; + /* error */ + if (pos >= 64) { + goto read_error; + } + pos1 = scan_table[pos]; + level = level << (shift_table[pos1] + shift_offset); + block[pos1] = level; + // printf("run=%d level=%d shift=%d\n", run, level, shift_table[pos1]); + } else { + if (re_index > last_index) + goto cannot_read; + /* level is zero: means run without coding. No + sign is coded */ + pos += run; + /* error */ + if (pos >= 64) { + read_error: +#if defined(VLC_DEBUG) || 1 + fprintf(stderr, "error pos=%d\n", pos); +#endif + /* for errors, we consider the eob is reached */ + mb->eob_reached = 1; + break; + } + } + } + CLOSE_READER(re, &s->gb); + mb->pos = pos; +} + +static inline void bit_copy(PutBitContext *pb, GetBitContext *gb, int bits_left) +{ + while (bits_left >= 16) { + put_bits(pb, 16, get_bits(gb, 16)); + bits_left -= 16; + } + if (bits_left > 0) { + put_bits(pb, bits_left, get_bits(gb, bits_left)); + } +} + +/* mb_x and mb_y are in units of 8 pixels */ +static inline void dv_decode_video_segment(DVVideoDecodeContext *s, + uint8_t *buf_ptr1, + const uint16_t *mb_pos_ptr) +{ + int quant, dc, dct_mode, class1, j; + int mb_index, mb_x, mb_y, v, last_index; + DCTELEM *block, *block1; + int c_offset, bits_left; + uint8_t *y_ptr; + BlockInfo mb_data[5 * 6], *mb, *mb1; + void (*idct_put)(uint8_t *dest, int line_size, DCTELEM *block); + uint8_t *buf_ptr; + PutBitContext pb, vs_pb; + uint8_t mb_bit_buffer[80 + 4]; /* allow some slack */ + int mb_bit_count; + uint8_t vs_bit_buffer[5 * 80 + 4]; /* allow some slack */ + int vs_bit_count; + + memset(s->block, 0, sizeof(s->block)); + + /* pass 1 : read DC and AC coefficients in blocks */ + buf_ptr = buf_ptr1; + block1 = &s->block[0][0]; + mb1 = mb_data; + init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80, NULL, NULL); + vs_bit_count = 0; + for(mb_index = 0; mb_index < 5; mb_index++) { + /* skip header */ + quant = buf_ptr[3] & 0x0f; + buf_ptr += 4; + init_put_bits(&pb, mb_bit_buffer, 80, NULL, NULL); + mb_bit_count = 0; + mb = mb1; + block = block1; + for(j = 0;j < 6; j++) { + /* NOTE: size is not important here */ + init_get_bits(&s->gb, buf_ptr, 14*8); + + /* get the dc */ + dc = get_bits(&s->gb, 9); + dc = (dc << (32 - 9)) >> (32 - 9); + dct_mode = get_bits1(&s->gb); + mb->dct_mode = dct_mode; + mb->scan_table = s->dv_zigzag[dct_mode]; + class1 = get_bits(&s->gb, 2); + mb->shift_offset = (class1 == 3); + mb->shift_table = s->dv_shift[dct_mode] + [quant + dv_quant_offset[class1]]; + dc = dc << 2; + /* convert to unsigned because 128 is not added in the + standard IDCT */ + dc += 1024; + block[0] = dc; + last_index = block_sizes[j]; + buf_ptr += last_index >> 3; + mb->pos = 0; + mb->partial_bit_count = 0; + + dv_decode_ac(s, mb, block, last_index); + + /* write the remaining bits in a new buffer only if the + block is finished */ + bits_left = last_index - get_bits_count(&s->gb); + if (mb->eob_reached) { + mb->partial_bit_count = 0; + mb_bit_count += bits_left; + bit_copy(&pb, &s->gb, bits_left); + } else { + /* should be < 16 bits otherwise a codeword could have + been parsed */ + mb->partial_bit_count = bits_left; + mb->partial_bit_buffer = get_bits(&s->gb, bits_left); + } + block += 64; + mb++; + } + + flush_put_bits(&pb); + + /* pass 2 : we can do it just after */ +#ifdef VLC_DEBUG + printf("***pass 2 size=%d\n", mb_bit_count); +#endif + block = block1; + mb = mb1; + init_get_bits(&s->gb, mb_bit_buffer, 80*8); + for(j = 0;j < 6; j++) { + if (!mb->eob_reached && get_bits_count(&s->gb) < mb_bit_count) { + dv_decode_ac(s, mb, block, mb_bit_count); + /* if still not finished, no need to parse other blocks */ + if (!mb->eob_reached) { + /* we could not parse the current AC coefficient, + so we add the remaining bytes */ + bits_left = mb_bit_count - get_bits_count(&s->gb); + if (bits_left > 0) { + mb->partial_bit_count += bits_left; + mb->partial_bit_buffer = + (mb->partial_bit_buffer << bits_left) | + get_bits(&s->gb, bits_left); + } + goto next_mb; + } + } + block += 64; + mb++; + } + /* all blocks are finished, so the extra bytes can be used at + the video segment level */ + bits_left = mb_bit_count - get_bits_count(&s->gb); + vs_bit_count += bits_left; + bit_copy(&vs_pb, &s->gb, bits_left); + next_mb: + mb1 += 6; + block1 += 6 * 64; + } + + /* we need a pass other the whole video segment */ + flush_put_bits(&vs_pb); + +#ifdef VLC_DEBUG + printf("***pass 3 size=%d\n", vs_bit_count); +#endif + block = &s->block[0][0]; + mb = mb_data; + init_get_bits(&s->gb, vs_bit_buffer, 5 * 80*8); + for(mb_index = 0; mb_index < 5; mb_index++) { + for(j = 0;j < 6; j++) { + if (!mb->eob_reached) { +#ifdef VLC_DEBUG + printf("start %d:%d\n", mb_index, j); +#endif + dv_decode_ac(s, mb, block, vs_bit_count); + } + block += 64; + mb++; + } + } + + /* compute idct and place blocks */ + block = &s->block[0][0]; + mb = mb_data; + for(mb_index = 0; mb_index < 5; mb_index++) { + v = *mb_pos_ptr++; + mb_x = v & 0xff; + mb_y = v >> 8; + y_ptr = s->current_picture[0] + (mb_y * s->linesize[0] * 8) + (mb_x * 8); + if (s->sampling_411) + c_offset = (mb_y * s->linesize[1] * 8) + ((mb_x >> 2) * 8); + else + c_offset = ((mb_y >> 1) * s->linesize[1] * 8) + ((mb_x >> 1) * 8); + for(j = 0;j < 6; j++) { + idct_put = s->idct_put[mb->dct_mode]; + if (j < 4) { + if (s->sampling_411 && mb_x < (704 / 8)) { + /* NOTE: at end of line, the macroblock is handled as 420 */ + idct_put(y_ptr + (j * 8), s->linesize[0], block); + } else { + idct_put(y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->linesize[0]), + s->linesize[0], block); + } + } else { + if (s->sampling_411 && mb_x >= (704 / 8)) { + uint8_t pixels[64], *c_ptr, *c_ptr1, *ptr; + int y, linesize; + /* NOTE: at end of line, the macroblock is handled as 420 */ + idct_put(pixels, 8, block); + linesize = s->linesize[6 - j]; + c_ptr = s->current_picture[6 - j] + c_offset; + ptr = pixels; + for(y = 0;y < 8; y++) { + /* convert to 411P */ + c_ptr1 = c_ptr + 8*linesize; + c_ptr[0]= ptr[0]; c_ptr1[0]= ptr[4]; + c_ptr[1]= ptr[1]; c_ptr1[1]= ptr[5]; + c_ptr[2]= ptr[2]; c_ptr1[2]= ptr[6]; + c_ptr[3]= ptr[3]; c_ptr1[3]= ptr[7]; + c_ptr += linesize; + ptr += 8; + } + } else { + /* don't ask me why they inverted Cb and Cr ! */ + idct_put(s->current_picture[6 - j] + c_offset, + s->linesize[6 - j], block); + } + } + block += 64; + mb++; + } + } +} + + +/* NOTE: exactly one frame must be given (120000 bytes for NTSC, + 144000 bytes for PAL) */ +static int dvvideo_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + DVVideoDecodeContext *s = avctx->priv_data; + int sct, dsf, apt, ds, nb_dif_segs, vs, width, height, i, packet_size; + uint8_t *buf_ptr; + const uint16_t *mb_pos_ptr; + + /* parse id */ + init_get_bits(&s->gb, buf, buf_size*8); + sct = get_bits(&s->gb, 3); + if (sct != 0) + return -1; + skip_bits(&s->gb, 5); + get_bits(&s->gb, 4); /* dsn (sequence number */ + get_bits(&s->gb, 1); /* fsc (channel number) */ + skip_bits(&s->gb, 3); + get_bits(&s->gb, 8); /* dbn (diff block number 0-134) */ + + dsf = get_bits(&s->gb, 1); /* 0 = NTSC 1 = PAL */ + if (get_bits(&s->gb, 1) != 0) + return -1; + skip_bits(&s->gb, 11); + apt = get_bits(&s->gb, 3); /* apt */ + + get_bits(&s->gb, 1); /* tf1 */ + skip_bits(&s->gb, 4); + get_bits(&s->gb, 3); /* ap1 */ + + get_bits(&s->gb, 1); /* tf2 */ + skip_bits(&s->gb, 4); + get_bits(&s->gb, 3); /* ap2 */ + + get_bits(&s->gb, 1); /* tf3 */ + skip_bits(&s->gb, 4); + get_bits(&s->gb, 3); /* ap3 */ + + /* init size */ + width = 720; + if (dsf) { + avctx->frame_rate = 25; + avctx->frame_rate_base = 1; + packet_size = PAL_FRAME_SIZE; + height = 576; + nb_dif_segs = 12; + } else { + avctx->frame_rate = 30000; + avctx->frame_rate_base = 1001; + packet_size = NTSC_FRAME_SIZE; + height = 480; + nb_dif_segs = 10; + } + /* NOTE: we only accept several full frames */ + if (buf_size < packet_size) + return -1; + + /* NTSC[dsf == 0] is always 720x480, 4:1:1 + * PAL[dsf == 1] is always 720x576, 4:2:0 for IEC 68134[apt == 0] + * but for the SMPTE 314M[apt == 1] it is 720x576, 4:1:1 + */ + s->sampling_411 = !dsf || apt; + if (s->sampling_411) { + mb_pos_ptr = dsf ? dv_place_411P : dv_place_411; + avctx->pix_fmt = PIX_FMT_YUV411P; + } else { + mb_pos_ptr = dv_place_420; + avctx->pix_fmt = PIX_FMT_YUV420P; + } + + avctx->width = width; + avctx->height = height; + + /* Once again, this is pretty complicated by the fact that the same + * field is used differently by IEC 68134[apt == 0] and + * SMPTE 314M[apt == 1]. + */ + if (buf[VAUX_TC61_OFFSET] == 0x61 && + ((apt == 0 && (buf[VAUX_TC61_OFFSET + 2] & 0x07) == 0x07) || + (apt == 1 && (buf[VAUX_TC61_OFFSET + 2] & 0x07) == 0x02))) + avctx->aspect_ratio = 16.0 / 9.0; + else + avctx->aspect_ratio = 4.0 / 3.0; + + if(s->picture.data[0]) + avctx->release_buffer(avctx, &s->picture); + + s->picture.reference= 0; + if(avctx->get_buffer(avctx, &s->picture) < 0) { + fprintf(stderr, "get_buffer() failed\n"); + return -1; + } + + for(i=0;i<3;i++) { + s->current_picture[i] = s->picture.data[i]; + s->linesize[i] = s->picture.linesize[i]; + if (!s->current_picture[i]) + return -1; + } + s->width = width; + s->height = height; + + /* for each DIF segment */ + buf_ptr = buf; + for (ds = 0; ds < nb_dif_segs; ds++) { + buf_ptr += 6 * 80; /* skip DIF segment header */ + + for(vs = 0; vs < 27; vs++) { + if ((vs % 3) == 0) { + /* skip audio block */ + buf_ptr += 80; + } + dv_decode_video_segment(s, buf_ptr, mb_pos_ptr); + buf_ptr += 5 * 80; + mb_pos_ptr += 5; + } + } + + emms_c(); + + /* return image */ + *data_size = sizeof(AVFrame); + *(AVFrame*)data= s->picture; + + return packet_size; +} + +static int dvvideo_decode_end(AVCodecContext *avctx) +{ + avcodec_default_free_buffers(avctx); + + return 0; +} + +AVCodec dvvideo_decoder = { + "dvvideo", + CODEC_TYPE_VIDEO, + CODEC_ID_DVVIDEO, + sizeof(DVVideoDecodeContext), + dvvideo_decode_init, + NULL, + dvvideo_decode_end, + dvvideo_decode_frame, + CODEC_CAP_DR1, + NULL +}; + +typedef struct DVAudioDecodeContext { + AVCodecContext *avctx; + GetBitContext gb; +} DVAudioDecodeContext; + +static int dvaudio_decode_init(AVCodecContext *avctx) +{ + // DVAudioDecodeContext *s = avctx->priv_data; + return 0; +} + +static uint16_t dv_audio_12to16(uint16_t sample) +{ + uint16_t shift, result; + + sample = (sample < 0x800) ? sample : sample | 0xf000; + shift = (sample & 0xf00) >> 8; + + if (shift < 0x2 || shift > 0xd) { + result = sample; + } else if (shift < 0x8) { + shift--; + result = (sample - (256 * shift)) << shift; + } else { + shift = 0xe - shift; + result = ((sample + ((256 * shift) + 1)) << shift) - 1; + } + + return result; +} + +/* NOTE: exactly one frame must be given (120000 bytes for NTSC, + 144000 bytes for PAL) + + There's a couple of assumptions being made here: + 1. By default we silence erroneous (0x8000/16bit 0x800/12bit) + audio samples. We can pass them upwards when ffmpeg will be ready + to deal with them. + 2. We don't do software emphasis. + 3. Audio is always returned as 16bit linear samples: 12bit + nonlinear samples are converted into 16bit linear ones. +*/ +static int dvaudio_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + DVVideoDecodeContext *s = avctx->priv_data; + const uint16_t (*unshuffle)[9]; + int smpls, freq, quant, sys, stride, difseg, ad, dp, nb_dif_segs, i; + uint16_t lc, rc; + uint8_t *buf_ptr; + + /* parse id */ + init_get_bits(&s->gb, &buf[AAUX_AS_OFFSET], 5*8); + i = get_bits(&s->gb, 8); + if (i != 0x50) { /* No audio ? */ + *data_size = 0; + return buf_size; + } + + get_bits(&s->gb, 1); /* 0 - locked audio, 1 - unlocked audio */ + skip_bits(&s->gb, 1); + smpls = get_bits(&s->gb, 6); /* samples in this frame - min. samples */ + + skip_bits(&s->gb, 8); + + skip_bits(&s->gb, 2); + sys = get_bits(&s->gb, 1); /* 0 - 60 fields, 1 = 50 fields */ + skip_bits(&s->gb, 5); + + get_bits(&s->gb, 1); /* 0 - emphasis on, 1 - emphasis off */ + get_bits(&s->gb, 1); /* 0 - reserved, 1 - emphasis time constant 50/15us */ + freq = get_bits(&s->gb, 3); /* 0 - 48KHz, 1 - 44,1kHz, 2 - 32 kHz */ + quant = get_bits(&s->gb, 3); /* 0 - 16bit linear, 1 - 12bit nonlinear */ + + if (quant > 1) + return -1; /* Unsupported quantization */ + + avctx->sample_rate = dv_audio_frequency[freq]; + avctx->channels = 2; + avctx->bit_rate = avctx->channels * avctx->sample_rate * 16; + // What about: + // avctx->frame_size = + + *data_size = (dv_audio_min_samples[sys][freq] + smpls) * + avctx->channels * 2; + + if (sys) { + nb_dif_segs = 12; + stride = 108; + unshuffle = dv_place_audio50; + } else { + nb_dif_segs = 10; + stride = 90; + unshuffle = dv_place_audio60; + } + + /* for each DIF segment */ + buf_ptr = buf; + for (difseg = 0; difseg < nb_dif_segs; difseg++) { + buf_ptr += 6 * 80; /* skip DIF segment header */ + for (ad = 0; ad < 9; ad++) { + + for (dp = 8; dp < 80; dp+=2) { + if (quant == 0) { /* 16bit quantization */ + i = unshuffle[difseg][ad] + (dp - 8)/2 * stride; + ((short *)data)[i] = (buf_ptr[dp] << 8) | buf_ptr[dp+1]; + if (((unsigned short *)data)[i] == 0x8000) + ((short *)data)[i] = 0; + } else { /* 12bit quantization */ + if (difseg >= nb_dif_segs/2) + goto out; /* We're not doing 4ch at this time */ + + lc = ((uint16_t)buf_ptr[dp] << 4) | + ((uint16_t)buf_ptr[dp+2] >> 4); + rc = ((uint16_t)buf_ptr[dp+1] << 4) | + ((uint16_t)buf_ptr[dp+2] & 0x0f); + lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc)); + rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc)); + + i = unshuffle[difseg][ad] + (dp - 8)/3 * stride; + ((short *)data)[i] = lc; + i = unshuffle[difseg+nb_dif_segs/2][ad] + (dp - 8)/3 * stride; + ((short *)data)[i] = rc; + ++dp; + } + } + + buf_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */ + } + } + +out: + return buf_size; +} + +static int dvaudio_decode_end(AVCodecContext *avctx) +{ + // DVAudioDecodeContext *s = avctx->priv_data; + return 0; +} + +AVCodec dvaudio_decoder = { + "dvaudio", + CODEC_TYPE_AUDIO, + CODEC_ID_DVAUDIO, + sizeof(DVAudioDecodeContext), + dvaudio_decode_init, + NULL, + dvaudio_decode_end, + dvaudio_decode_frame, + 0, + NULL +};