yading@10: /*
yading@10:  * Linux audio play and grab interface
yading@10:  * Copyright (c) 2000, 2001 Fabrice Bellard
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 "config.h"
yading@10: #include <stdlib.h>
yading@10: #include <stdio.h>
yading@10: #include <stdint.h>
yading@10: #include <string.h>
yading@10: #include <errno.h>
yading@10: #if HAVE_SOUNDCARD_H
yading@10: #include <soundcard.h>
yading@10: #else
yading@10: #include <sys/soundcard.h>
yading@10: #endif
yading@10: #include <unistd.h>
yading@10: #include <fcntl.h>
yading@10: #include <sys/ioctl.h>
yading@10: 
yading@10: #include "libavutil/log.h"
yading@10: #include "libavutil/opt.h"
yading@10: #include "libavutil/time.h"
yading@10: #include "libavcodec/avcodec.h"
yading@10: #include "avdevice.h"
yading@10: #include "libavformat/internal.h"
yading@10: 
yading@10: #define AUDIO_BLOCK_SIZE 4096
yading@10: 
yading@10: typedef struct {
yading@10:     AVClass *class;
yading@10:     int fd;
yading@10:     int sample_rate;
yading@10:     int channels;
yading@10:     int frame_size; /* in bytes ! */
yading@10:     enum AVCodecID codec_id;
yading@10:     unsigned int flip_left : 1;
yading@10:     uint8_t buffer[AUDIO_BLOCK_SIZE];
yading@10:     int buffer_ptr;
yading@10: } AudioData;
yading@10: 
yading@10: static int audio_open(AVFormatContext *s1, int is_output, const char *audio_device)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10:     int audio_fd;
yading@10:     int tmp, err;
yading@10:     char *flip = getenv("AUDIO_FLIP_LEFT");
yading@10: 
yading@10:     if (is_output)
yading@10:         audio_fd = open(audio_device, O_WRONLY);
yading@10:     else
yading@10:         audio_fd = open(audio_device, O_RDONLY);
yading@10:     if (audio_fd < 0) {
yading@10:         av_log(s1, AV_LOG_ERROR, "%s: %s\n", audio_device, strerror(errno));
yading@10:         return AVERROR(EIO);
yading@10:     }
yading@10: 
yading@10:     if (flip && *flip == '1') {
yading@10:         s->flip_left = 1;
yading@10:     }
yading@10: 
yading@10:     /* non blocking mode */
yading@10:     if (!is_output) {
yading@10:         if (fcntl(audio_fd, F_SETFL, O_NONBLOCK) < 0) {
yading@10:             av_log(s1, AV_LOG_WARNING, "%s: Could not enable non block mode (%s)\n", audio_device, strerror(errno));
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     s->frame_size = AUDIO_BLOCK_SIZE;
yading@10: 
yading@10:     /* select format : favour native format */
yading@10:     err = ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &tmp);
yading@10: 
yading@10: #if HAVE_BIGENDIAN
yading@10:     if (tmp & AFMT_S16_BE) {
yading@10:         tmp = AFMT_S16_BE;
yading@10:     } else if (tmp & AFMT_S16_LE) {
yading@10:         tmp = AFMT_S16_LE;
yading@10:     } else {
yading@10:         tmp = 0;
yading@10:     }
yading@10: #else
yading@10:     if (tmp & AFMT_S16_LE) {
yading@10:         tmp = AFMT_S16_LE;
yading@10:     } else if (tmp & AFMT_S16_BE) {
yading@10:         tmp = AFMT_S16_BE;
yading@10:     } else {
yading@10:         tmp = 0;
yading@10:     }
yading@10: #endif
yading@10: 
yading@10:     switch(tmp) {
yading@10:     case AFMT_S16_LE:
yading@10:         s->codec_id = AV_CODEC_ID_PCM_S16LE;
yading@10:         break;
yading@10:     case AFMT_S16_BE:
yading@10:         s->codec_id = AV_CODEC_ID_PCM_S16BE;
yading@10:         break;
yading@10:     default:
yading@10:         av_log(s1, AV_LOG_ERROR, "Soundcard does not support 16 bit sample format\n");
yading@10:         close(audio_fd);
yading@10:         return AVERROR(EIO);
yading@10:     }
yading@10:     err=ioctl(audio_fd, SNDCTL_DSP_SETFMT, &tmp);
yading@10:     if (err < 0) {
yading@10:         av_log(s1, AV_LOG_ERROR, "SNDCTL_DSP_SETFMT: %s\n", strerror(errno));
yading@10:         goto fail;
yading@10:     }
yading@10: 
yading@10:     tmp = (s->channels == 2);
yading@10:     err = ioctl(audio_fd, SNDCTL_DSP_STEREO, &tmp);
yading@10:     if (err < 0) {
yading@10:         av_log(s1, AV_LOG_ERROR, "SNDCTL_DSP_STEREO: %s\n", strerror(errno));
yading@10:         goto fail;
yading@10:     }
yading@10: 
yading@10:     tmp = s->sample_rate;
yading@10:     err = ioctl(audio_fd, SNDCTL_DSP_SPEED, &tmp);
yading@10:     if (err < 0) {
yading@10:         av_log(s1, AV_LOG_ERROR, "SNDCTL_DSP_SPEED: %s\n", strerror(errno));
yading@10:         goto fail;
yading@10:     }
yading@10:     s->sample_rate = tmp; /* store real sample rate */
yading@10:     s->fd = audio_fd;
yading@10: 
yading@10:     return 0;
yading@10:  fail:
yading@10:     close(audio_fd);
yading@10:     return AVERROR(EIO);
yading@10: }
yading@10: 
yading@10: static int audio_close(AudioData *s)
yading@10: {
yading@10:     close(s->fd);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /* sound output support */
yading@10: static int audio_write_header(AVFormatContext *s1)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10:     AVStream *st;
yading@10:     int ret;
yading@10: 
yading@10:     st = s1->streams[0];
yading@10:     s->sample_rate = st->codec->sample_rate;
yading@10:     s->channels = st->codec->channels;
yading@10:     ret = audio_open(s1, 1, s1->filename);
yading@10:     if (ret < 0) {
yading@10:         return AVERROR(EIO);
yading@10:     } else {
yading@10:         return 0;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static int audio_write_packet(AVFormatContext *s1, AVPacket *pkt)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10:     int len, ret;
yading@10:     int size= pkt->size;
yading@10:     uint8_t *buf= pkt->data;
yading@10: 
yading@10:     while (size > 0) {
yading@10:         len = FFMIN(AUDIO_BLOCK_SIZE - s->buffer_ptr, size);
yading@10:         memcpy(s->buffer + s->buffer_ptr, buf, len);
yading@10:         s->buffer_ptr += len;
yading@10:         if (s->buffer_ptr >= AUDIO_BLOCK_SIZE) {
yading@10:             for(;;) {
yading@10:                 ret = write(s->fd, s->buffer, AUDIO_BLOCK_SIZE);
yading@10:                 if (ret > 0)
yading@10:                     break;
yading@10:                 if (ret < 0 && (errno != EAGAIN && errno != EINTR))
yading@10:                     return AVERROR(EIO);
yading@10:             }
yading@10:             s->buffer_ptr = 0;
yading@10:         }
yading@10:         buf += len;
yading@10:         size -= len;
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int audio_write_trailer(AVFormatContext *s1)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10: 
yading@10:     audio_close(s);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /* grab support */
yading@10: 
yading@10: static int audio_read_header(AVFormatContext *s1)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10:     AVStream *st;
yading@10:     int ret;
yading@10: 
yading@10:     st = avformat_new_stream(s1, NULL);
yading@10:     if (!st) {
yading@10:         return AVERROR(ENOMEM);
yading@10:     }
yading@10: 
yading@10:     ret = audio_open(s1, 0, s1->filename);
yading@10:     if (ret < 0) {
yading@10:         return AVERROR(EIO);
yading@10:     }
yading@10: 
yading@10:     /* take real parameters */
yading@10:     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
yading@10:     st->codec->codec_id = s->codec_id;
yading@10:     st->codec->sample_rate = s->sample_rate;
yading@10:     st->codec->channels = s->channels;
yading@10: 
yading@10:     avpriv_set_pts_info(st, 64, 1, 1000000);  /* 64 bits pts in us */
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int audio_read_packet(AVFormatContext *s1, AVPacket *pkt)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10:     int ret, bdelay;
yading@10:     int64_t cur_time;
yading@10:     struct audio_buf_info abufi;
yading@10: 
yading@10:     if ((ret=av_new_packet(pkt, s->frame_size)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     ret = read(s->fd, pkt->data, pkt->size);
yading@10:     if (ret <= 0){
yading@10:         av_free_packet(pkt);
yading@10:         pkt->size = 0;
yading@10:         if (ret<0)  return AVERROR(errno);
yading@10:         else        return AVERROR_EOF;
yading@10:     }
yading@10:     pkt->size = ret;
yading@10: 
yading@10:     /* compute pts of the start of the packet */
yading@10:     cur_time = av_gettime();
yading@10:     bdelay = ret;
yading@10:     if (ioctl(s->fd, SNDCTL_DSP_GETISPACE, &abufi) == 0) {
yading@10:         bdelay += abufi.bytes;
yading@10:     }
yading@10:     /* subtract time represented by the number of bytes in the audio fifo */
yading@10:     cur_time -= (bdelay * 1000000LL) / (s->sample_rate * s->channels);
yading@10: 
yading@10:     /* convert to wanted units */
yading@10:     pkt->pts = cur_time;
yading@10: 
yading@10:     if (s->flip_left && s->channels == 2) {
yading@10:         int i;
yading@10:         short *p = (short *) pkt->data;
yading@10: 
yading@10:         for (i = 0; i < ret; i += 4) {
yading@10:             *p = ~*p;
yading@10:             p += 2;
yading@10:         }
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int audio_read_close(AVFormatContext *s1)
yading@10: {
yading@10:     AudioData *s = s1->priv_data;
yading@10: 
yading@10:     audio_close(s);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: #if CONFIG_OSS_INDEV
yading@10: static const AVOption options[] = {
yading@10:     { "sample_rate", "", offsetof(AudioData, sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
yading@10:     { "channels",    "", offsetof(AudioData, channels),    AV_OPT_TYPE_INT, {.i64 = 2},     1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
yading@10:     { NULL },
yading@10: };
yading@10: 
yading@10: static const AVClass oss_demuxer_class = {
yading@10:     .class_name     = "OSS demuxer",
yading@10:     .item_name      = av_default_item_name,
yading@10:     .option         = options,
yading@10:     .version        = LIBAVUTIL_VERSION_INT,
yading@10: };
yading@10: 
yading@10: AVInputFormat ff_oss_demuxer = {
yading@10:     .name           = "oss",
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("OSS (Open Sound System) capture"),
yading@10:     .priv_data_size = sizeof(AudioData),
yading@10:     .read_header    = audio_read_header,
yading@10:     .read_packet    = audio_read_packet,
yading@10:     .read_close     = audio_read_close,
yading@10:     .flags          = AVFMT_NOFILE,
yading@10:     .priv_class     = &oss_demuxer_class,
yading@10: };
yading@10: #endif
yading@10: 
yading@10: #if CONFIG_OSS_OUTDEV
yading@10: AVOutputFormat ff_oss_muxer = {
yading@10:     .name           = "oss",
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("OSS (Open Sound System) playback"),
yading@10:     .priv_data_size = sizeof(AudioData),
yading@10:     /* XXX: we make the assumption that the soundcard accepts this format */
yading@10:     /* XXX: find better solution with "preinit" method, needed also in
yading@10:        other formats */
yading@10:     .audio_codec    = AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE),
yading@10:     .video_codec    = AV_CODEC_ID_NONE,
yading@10:     .write_header   = audio_write_header,
yading@10:     .write_packet   = audio_write_packet,
yading@10:     .write_trailer  = audio_write_trailer,
yading@10:     .flags          = AVFMT_NOFILE,
yading@10: };
yading@10: #endif