/* * 4X Technologies .4xm File Demuxer (no muxer) * Copyright (c) 2003 The ffmpeg Project * * 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 4xm.c * 4X Technologies file demuxer * by Mike Melanson (melanson@pcisys.net) * for more information on the .4xm file format, visit: * http://www.pcisys.net/~melanson/codecs/ */ #include "avformat.h" #define RIFF_TAG MKTAG('R', 'I', 'F', 'F') #define _4XMV_TAG MKTAG('4', 'X', 'M', 'V') #define LIST_TAG MKTAG('L', 'I', 'S', 'T') #define HEAD_TAG MKTAG('H', 'E', 'A', 'D') #define TRK__TAG MKTAG('T', 'R', 'K', '_') #define MOVI_TAG MKTAG('M', 'O', 'V', 'I') #define VTRK_TAG MKTAG('V', 'T', 'R', 'K') #define STRK_TAG MKTAG('S', 'T', 'R', 'K') #define std__TAG MKTAG('s', 't', 'd', '_') #define name_TAG MKTAG('n', 'a', 'm', 'e') #define vtrk_TAG MKTAG('v', 't', 'r', 'k') #define strk_TAG MKTAG('s', 't', 'r', 'k') #define ifrm_TAG MKTAG('i', 'f', 'r', 'm') #define pfrm_TAG MKTAG('p', 'f', 'r', 'm') #define cfrm_TAG MKTAG('c', 'f', 'r', 'm') #define snd__TAG MKTAG('s', 'n', 'd', '_') #define vtrk_SIZE 0x44 #define strk_SIZE 0x28 #define GET_LIST_HEADER() \ fourcc_tag = get_le32(pb); \ size = get_le32(pb); \ if (fourcc_tag != LIST_TAG) \ return AVERROR_INVALIDDATA; \ fourcc_tag = get_le32(pb); typedef struct AudioTrack { int sample_rate; int bits; int channels; int stream_index; int adpcm; } AudioTrack; typedef struct FourxmDemuxContext { int width; int height; int video_stream_index; int track_count; AudioTrack *tracks; int selected_track; int64_t audio_pts; int64_t video_pts; int video_pts_inc; float fps; } FourxmDemuxContext; static float get_le_float(unsigned char *buffer) { float f; unsigned char *float_buffer = (unsigned char *)&f; #ifdef WORDS_BIGENDIAN float_buffer[0] = buffer[3]; float_buffer[1] = buffer[2]; float_buffer[2] = buffer[1]; float_buffer[3] = buffer[0]; #else float_buffer[0] = buffer[0]; float_buffer[1] = buffer[1]; float_buffer[2] = buffer[2]; float_buffer[3] = buffer[3]; #endif return f; } static int fourxm_probe(AVProbeData *p) { if (p->buf_size < 12) return 0; if ((LE_32(&p->buf[0]) != RIFF_TAG) || (LE_32(&p->buf[8]) != _4XMV_TAG)) return 0; return AVPROBE_SCORE_MAX; } static int fourxm_read_header(AVFormatContext *s, AVFormatParameters *ap) { ByteIOContext *pb = &s->pb; unsigned int fourcc_tag; unsigned int size; int header_size; FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data; unsigned char *header; int i; int current_track = -1; AVStream *st; fourxm->track_count = 0; fourxm->tracks = NULL; fourxm->selected_track = 0; fourxm->fps = 1.0; /* skip the first 3 32-bit numbers */ url_fseek(pb, 12, SEEK_CUR); /* check for LIST-HEAD */ GET_LIST_HEADER(); header_size = size - 4; if (fourcc_tag != HEAD_TAG) return AVERROR_INVALIDDATA; /* allocate space for the header and load the whole thing */ header = av_malloc(header_size); if (!header) return AVERROR_NOMEM; if (get_buffer(pb, header, header_size) != header_size) return AVERROR_IO; /* take the lazy approach and search for any and all vtrk and strk chunks */ for (i = 0; i < header_size - 8; i++) { fourcc_tag = LE_32(&header[i]); size = LE_32(&header[i + 4]); if (fourcc_tag == std__TAG) { fourxm->fps = get_le_float(&header[i + 12]); fourxm->video_pts_inc = (int)(90000.0 / fourxm->fps); } else if (fourcc_tag == vtrk_TAG) { /* check that there is enough data */ if (size != vtrk_SIZE) { av_free(header); return AVERROR_INVALIDDATA; } fourxm->width = LE_32(&header[i + 36]); fourxm->height = LE_32(&header[i + 40]); i += 8 + size; /* allocate a new AVStream */ st = av_new_stream(s, 0); if (!st) return AVERROR_NOMEM; av_set_pts_info(st, 33, 1, 90000); fourxm->video_stream_index = st->index; st->codec.frame_rate = fourxm->fps; st->codec.frame_rate_base = 1.0; st->codec.codec_type = CODEC_TYPE_VIDEO; st->codec.codec_id = CODEC_ID_4XM; st->codec.codec_tag = 0; /* no fourcc */ st->codec.width = fourxm->width; st->codec.height = fourxm->height; } else if (fourcc_tag == strk_TAG) { /* check that there is enough data */ if (size != strk_SIZE) { av_free(header); return AVERROR_INVALIDDATA; } current_track = LE_32(&header[i + 8]); if (current_track + 1 > fourxm->track_count) { fourxm->track_count = current_track + 1; fourxm->tracks = av_realloc(fourxm->tracks, fourxm->track_count * sizeof(AudioTrack)); if (!fourxm->tracks) { av_free(header); return AVERROR_NOMEM; } } fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]); fourxm->tracks[current_track].channels = LE_32(&header[i + 36]); fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]); fourxm->tracks[current_track].bits = LE_32(&header[i + 44]); i += 8 + size; /* allocate a new AVStream */ st = av_new_stream(s, current_track); if (!st) return AVERROR_NOMEM; /* set the pts reference (1 pts = 1/90000) */ av_set_pts_info(st, 33, 1, 90000); fourxm->tracks[current_track].stream_index = st->index; st->codec.codec_type = CODEC_TYPE_AUDIO; st->codec.codec_tag = 1; st->codec.channels = fourxm->tracks[current_track].channels; st->codec.sample_rate = fourxm->tracks[current_track].sample_rate; st->codec.bits_per_sample = fourxm->tracks[current_track].bits; st->codec.bit_rate = st->codec.channels * st->codec.sample_rate * st->codec.bits_per_sample; st->codec.block_align = st->codec.channels * st->codec.bits_per_sample; if (fourxm->tracks[current_track].adpcm) st->codec.codec_id = CODEC_ID_ADPCM_4XM; else if (st->codec.bits_per_sample == 8) st->codec.codec_id = CODEC_ID_PCM_U8; else st->codec.codec_id = CODEC_ID_PCM_S16LE; } } av_free(header); /* skip over the LIST-MOVI chunk (which is where the stream should be */ GET_LIST_HEADER(); if (fourcc_tag != MOVI_TAG) return AVERROR_INVALIDDATA; /* initialize context members */ fourxm->video_pts = -fourxm->video_pts_inc; /* first frame will push to 0 */ fourxm->audio_pts = 0; return 0; } static int fourxm_read_packet(AVFormatContext *s, AVPacket *pkt) { FourxmDemuxContext *fourxm = s->priv_data; ByteIOContext *pb = &s->pb; unsigned int fourcc_tag; unsigned int size, out_size; int ret = 0; int track_number; int packet_read = 0; unsigned char header[8]; int64_t pts_inc; int audio_frame_count; while (!packet_read) { if ((ret = get_buffer(&s->pb, header, 8)) < 0) return ret; fourcc_tag = LE_32(&header[0]); size = LE_32(&header[4]); if (url_feof(pb)) return AVERROR_IO; switch (fourcc_tag) { case LIST_TAG: /* this is a good time to bump the video pts */ fourxm->video_pts += fourxm->video_pts_inc; /* skip the LIST-* tag and move on to the next fourcc */ get_le32(pb); break; case ifrm_TAG: case pfrm_TAG: case cfrm_TAG:{ /* allocate 8 more bytes than 'size' to account for fourcc * and size */ if (av_new_packet(pkt, size + 8)) return AVERROR_IO; pkt->stream_index = fourxm->video_stream_index; pkt->pts = fourxm->video_pts; memcpy(pkt->data, header, 8); ret = get_buffer(&s->pb, &pkt->data[8], size); if (ret < 0) av_free_packet(pkt); else packet_read = 1; break; } case snd__TAG: track_number = get_le32(pb); out_size= get_le32(pb); size-=8; if (track_number == fourxm->selected_track) { if (av_new_packet(pkt, size)) return AVERROR_IO; pkt->stream_index = fourxm->tracks[fourxm->selected_track].stream_index; pkt->pts = fourxm->audio_pts; ret = get_buffer(&s->pb, pkt->data, size); if (ret < 0) av_free_packet(pkt); else packet_read = 1; /* pts accounting */ audio_frame_count = size; if (fourxm->tracks[fourxm->selected_track].adpcm) audio_frame_count -= 2 * (fourxm->tracks[fourxm->selected_track].channels); audio_frame_count /= fourxm->tracks[fourxm->selected_track].channels; if (fourxm->tracks[fourxm->selected_track].adpcm) audio_frame_count *= 2; else audio_frame_count /= (fourxm->tracks[fourxm->selected_track].bits / 8); pts_inc = audio_frame_count; pts_inc *= 90000; pts_inc /= fourxm->tracks[fourxm->selected_track].sample_rate; fourxm->audio_pts += pts_inc; } else { url_fseek(pb, size, SEEK_CUR); } break; default: url_fseek(pb, size, SEEK_CUR); break; } } return ret; } static int fourxm_read_close(AVFormatContext *s) { FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data; av_free(fourxm->tracks); return 0; } static AVInputFormat fourxm_iformat = { "4xm", "4X Technologies format", sizeof(FourxmDemuxContext), fourxm_probe, fourxm_read_header, fourxm_read_packet, fourxm_read_close, }; int fourxm_init(void) { av_register_input_format(&fourxm_iformat); return 0; }