/* * Copyright (c) 2012 Andrew D'Addesio * Copyright (c) 2013-2014 Mozilla Corporation * * 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 * Opus decoder/parser shared code */ #include <stdint.h> #include "libavutil/error.h" #include "libavutil/ffmath.h" #include "opus.h" #include "vorbis.h" static const uint16_t opus_frame_duration[32] = { 480, 960, 1920, 2880, 480, 960, 1920, 2880, 480, 960, 1920, 2880, 480, 960, 480, 960, 120, 240, 480, 960, 120, 240, 480, 960, 120, 240, 480, 960, 120, 240, 480, 960, }; /** * Read a 1- or 2-byte frame length */ static inline int xiph_lacing_16bit(const uint8_t **ptr, const uint8_t *end) { int val; if (*ptr >= end) return AVERROR_INVALIDDATA; val = *(*ptr)++; if (val >= 252) { if (*ptr >= end) return AVERROR_INVALIDDATA; val += 4 * *(*ptr)++; } return val; } /** * Read a multi-byte length (used for code 3 packet padding size) */ static inline int xiph_lacing_full(const uint8_t **ptr, const uint8_t *end) { int val = 0; int next; while (1) { if (*ptr >= end || val > INT_MAX - 254) return AVERROR_INVALIDDATA; next = *(*ptr)++; val += next; if (next < 255) break; else val--; } return val; } /** * Parse Opus packet info from raw packet data */ int ff_opus_parse_packet(OpusPacket *pkt, const uint8_t *buf, int buf_size, int self_delimiting) { const uint8_t *ptr = buf; const uint8_t *end = buf + buf_size; int padding = 0; int frame_bytes, i; if (buf_size < 1) goto fail; /* TOC byte */ i = *ptr++; pkt->code = (i ) & 0x3; pkt->stereo = (i >> 2) & 0x1; pkt->config = (i >> 3) & 0x1F; /* code 2 and code 3 packets have at least 1 byte after the TOC */ if (pkt->code >= 2 && buf_size < 2) goto fail; switch (pkt->code) { case 0: /* 1 frame */ pkt->frame_count = 1; pkt->vbr = 0; if (self_delimiting) { int len = xiph_lacing_16bit(&ptr, end); if (len < 0 || len > end - ptr) goto fail; end = ptr + len; buf_size = end - buf; } frame_bytes = end - ptr; if (frame_bytes > MAX_FRAME_SIZE) goto fail; pkt->frame_offset[0] = ptr - buf; pkt->frame_size[0] = frame_bytes; break; case 1: /* 2 frames, equal size */ pkt->frame_count = 2; pkt->vbr = 0; if (self_delimiting) { int len = xiph_lacing_16bit(&ptr, end); if (len < 0 || 2 * len > end - ptr) goto fail; end = ptr + 2 * len; buf_size = end - buf; } frame_bytes = end - ptr; if (frame_bytes & 1 || frame_bytes >> 1 > MAX_FRAME_SIZE) goto fail; pkt->frame_offset[0] = ptr - buf; pkt->frame_size[0] = frame_bytes >> 1; pkt->frame_offset[1] = pkt->frame_offset[0] + pkt->frame_size[0]; pkt->frame_size[1] = frame_bytes >> 1; break; case 2: /* 2 frames, different sizes */ pkt->frame_count = 2; pkt->vbr = 1; /* read 1st frame size */ frame_bytes = xiph_lacing_16bit(&ptr, end); if (frame_bytes < 0) goto fail; if (self_delimiting) { int len = xiph_lacing_16bit(&ptr, end); if (len < 0 || len + frame_bytes > end - ptr) goto fail; end = ptr + frame_bytes + len; buf_size = end - buf; } pkt->frame_offset[0] = ptr - buf; pkt->frame_size[0] = frame_bytes; /* calculate 2nd frame size */ frame_bytes = end - ptr - pkt->frame_size[0]; if (frame_bytes < 0 || frame_bytes > MAX_FRAME_SIZE) goto fail; pkt->frame_offset[1] = pkt->frame_offset[0] + pkt->frame_size[0]; pkt->frame_size[1] = frame_bytes; break; case 3: /* 1 to 48 frames, can be different sizes */ i = *ptr++; pkt->frame_count = (i ) & 0x3F; padding = (i >> 6) & 0x01; pkt->vbr = (i >> 7) & 0x01; if (pkt->frame_count == 0 || pkt->frame_count > MAX_FRAMES) goto fail; /* read padding size */ if (padding) { padding = xiph_lacing_full(&ptr, end); if (padding < 0) goto fail; } /* read frame sizes */ if (pkt->vbr) { /* for VBR, all frames except the final one have their size coded in the bitstream. the last frame size is implicit. */ int total_bytes = 0; for (i = 0; i < pkt->frame_count - 1; i++) { frame_bytes = xiph_lacing_16bit(&ptr, end); if (frame_bytes < 0) goto fail; pkt->frame_size[i] = frame_bytes; total_bytes += frame_bytes; } if (self_delimiting) { int len = xiph_lacing_16bit(&ptr, end); if (len < 0 || len + total_bytes + padding > end - ptr) goto fail; end = ptr + total_bytes + len + padding; buf_size = end - buf; } frame_bytes = end - ptr - padding; if (total_bytes > frame_bytes) goto fail; pkt->frame_offset[0] = ptr - buf; for (i = 1; i < pkt->frame_count; i++) pkt->frame_offset[i] = pkt->frame_offset[i-1] + pkt->frame_size[i-1]; pkt->frame_size[pkt->frame_count-1] = frame_bytes - total_bytes; } else { /* for CBR, the remaining packet bytes are divided evenly between the frames */ if (self_delimiting) { frame_bytes = xiph_lacing_16bit(&ptr, end); if (frame_bytes < 0 || pkt->frame_count * frame_bytes + padding > end - ptr) goto fail; end = ptr + pkt->frame_count * frame_bytes + padding; buf_size = end - buf; } else { frame_bytes = end - ptr - padding; if (frame_bytes % pkt->frame_count || frame_bytes / pkt->frame_count > MAX_FRAME_SIZE) goto fail; frame_bytes /= pkt->frame_count; } pkt->frame_offset[0] = ptr - buf; pkt->frame_size[0] = frame_bytes; for (i = 1; i < pkt->frame_count; i++) { pkt->frame_offset[i] = pkt->frame_offset[i-1] + pkt->frame_size[i-1]; pkt->frame_size[i] = frame_bytes; } } } pkt->packet_size = buf_size; pkt->data_size = pkt->packet_size - padding; /* total packet duration cannot be larger than 120ms */ pkt->frame_duration = opus_frame_duration[pkt->config]; if (pkt->frame_duration * pkt->frame_count > MAX_PACKET_DUR) goto fail; /* set mode and bandwidth */ if (pkt->config < 12) { pkt->mode = OPUS_MODE_SILK; pkt->bandwidth = pkt->config >> 2; } else if (pkt->config < 16) { pkt->mode = OPUS_MODE_HYBRID; pkt->bandwidth = OPUS_BANDWIDTH_SUPERWIDEBAND + (pkt->config >= 14); } else { pkt->mode = OPUS_MODE_CELT; pkt->bandwidth = (pkt->config - 16) >> 2; /* skip medium band */ if (pkt->bandwidth) pkt->bandwidth++; } return 0; fail: memset(pkt, 0, sizeof(*pkt)); return AVERROR_INVALIDDATA; } static int channel_reorder_vorbis(int nb_channels, int channel_idx) { return ff_vorbis_channel_layout_offsets[nb_channels - 1][channel_idx]; } static int channel_reorder_unknown(int nb_channels, int channel_idx) { return channel_idx; } av_cold int ff_opus_parse_extradata(AVCodecContext *avctx, OpusContext *s) { static const uint8_t default_channel_map[2] = { 0, 1 }; int (*channel_reorder)(int, int) = channel_reorder_unknown; const uint8_t *extradata, *channel_map; int extradata_size; int version, channels, map_type, streams, stereo_streams, i, j; uint64_t layout; if (!avctx->extradata) { if (avctx->channels > 2) { av_log(avctx, AV_LOG_ERROR, "Multichannel configuration without extradata.\n"); return AVERROR(EINVAL); } extradata = opus_default_extradata; extradata_size = sizeof(opus_default_extradata); } else { extradata = avctx->extradata; extradata_size = avctx->extradata_size; } if (extradata_size < 19) { av_log(avctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", extradata_size); return AVERROR_INVALIDDATA; } version = extradata[8]; if (version > 15) { avpriv_request_sample(avctx, "Extradata version %d", version); return AVERROR_PATCHWELCOME; } avctx->delay = AV_RL16(extradata + 10); channels = avctx->extradata ? extradata[9] : (avctx->channels == 1) ? 1 : 2; if (!channels) { av_log(avctx, AV_LOG_ERROR, "Zero channel count specified in the extradata\n"); return AVERROR_INVALIDDATA; } s->gain_i = AV_RL16(extradata + 16); if (s->gain_i) s->gain = ff_exp10(s->gain_i / (20.0 * 256)); map_type = extradata[18]; if (!map_type) { if (channels > 2) { av_log(avctx, AV_LOG_ERROR, "Channel mapping 0 is only specified for up to 2 channels\n"); return AVERROR_INVALIDDATA; } layout = (channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO; streams = 1; stereo_streams = channels - 1; channel_map = default_channel_map; } else if (map_type == 1 || map_type == 2 || map_type == 255) { if (extradata_size < 21 + channels) { av_log(avctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", extradata_size); return AVERROR_INVALIDDATA; } streams = extradata[19]; stereo_streams = extradata[20]; if (!streams || stereo_streams > streams || streams + stereo_streams > 255) { av_log(avctx, AV_LOG_ERROR, "Invalid stream/stereo stream count: %d/%d\n", streams, stereo_streams); return AVERROR_INVALIDDATA; } if (map_type == 1) { if (channels > 8) { av_log(avctx, AV_LOG_ERROR, "Channel mapping 1 is only specified for up to 8 channels\n"); return AVERROR_INVALIDDATA; } layout = ff_vorbis_channel_layouts[channels - 1]; channel_reorder = channel_reorder_vorbis; } else if (map_type == 2) { int ambisonic_order = ff_sqrt(channels) - 1; if (channels != ((ambisonic_order + 1) * (ambisonic_order + 1)) && channels != ((ambisonic_order + 1) * (ambisonic_order + 1) + 2)) { av_log(avctx, AV_LOG_ERROR, "Channel mapping 2 is only specified for channel counts" " which can be written as (n + 1)^2 or (n + 1)^2 + 2" " for nonnegative integer n\n"); return AVERROR_INVALIDDATA; } if (channels > 227) { av_log(avctx, AV_LOG_ERROR, "Too many channels\n"); return AVERROR_INVALIDDATA; } layout = 0; } else layout = 0; channel_map = extradata + 21; } else { avpriv_request_sample(avctx, "Mapping type %d", map_type); return AVERROR_PATCHWELCOME; } s->channel_maps = av_mallocz_array(channels, sizeof(*s->channel_maps)); if (!s->channel_maps) return AVERROR(ENOMEM); for (i = 0; i < channels; i++) { ChannelMap *map = &s->channel_maps[i]; uint8_t idx = channel_map[channel_reorder(channels, i)]; if (idx == 255) { map->silence = 1; continue; } else if (idx >= streams + stereo_streams) { av_log(avctx, AV_LOG_ERROR, "Invalid channel map for output channel %d: %d\n", i, idx); av_freep(&s->channel_maps); return AVERROR_INVALIDDATA; } /* check that we did not see this index yet */ map->copy = 0; for (j = 0; j < i; j++) if (channel_map[channel_reorder(channels, j)] == idx) { map->copy = 1; map->copy_idx = j; break; } if (idx < 2 * stereo_streams) { map->stream_idx = idx / 2; map->channel_idx = idx & 1; } else { map->stream_idx = idx - stereo_streams; map->channel_idx = 0; } } avctx->channels = channels; avctx->channel_layout = layout; s->nb_streams = streams; s->nb_stereo_streams = stereo_streams; return 0; }