ffs.c

   1 #include <fcntl.h>
   2 #include <stdlib.h>
   3 #include <stdint.h>
   4 #include <unistd.h>
   5 #include <sys/time.h>
   6 #include <libavformat/avformat.h>
   7 #include <libavcodec/avcodec.h>
   8 #include <libswscale/swscale.h>
   9 #include "ffs.h"
  10
  11 /* ffmpeg stream */
  12 struct ffs {
  13         AVCodecContext *cc;
  14         AVFormatContext *fc;
  15         AVPacket pkt;
  16         int si;                 /* stream index */
  17         long ts;                /* frame timestamp (ms) */
  18         long seq;               /* current position in this stream */
  19         long seq_all;           /* seen packets after ffs_seek() */
  20         long seq_cur;           /* decoded packet after ffs_seek() */
  21
  22         /* decoding video frames */
  23         struct SwsContext *swsc;
  24         AVFrame *dst;
  25         AVFrame *tmp;
  26 };
  27
  28 struct ffs *ffs_alloc(char *path, int video)
  29 {
  30         struct ffs *ffs;
  31         int codec_type = video ? CODEC_TYPE_VIDEO : CODEC_TYPE_AUDIO;
  32         int i;
  33         ffs = malloc(sizeof(*ffs));
  34         memset(ffs, 0, sizeof(*ffs));
  35         ffs->si = -1;
  36         if (av_open_input_file(&ffs->fc, path, NULL, 0, NULL))
  37                 goto failed;
  38         if (av_find_stream_info(ffs->fc) < 0)
  39                 goto failed;
  40         for (i = 0; i < ffs->fc->nb_streams; i++)
  41                 if (ffs->fc->streams[i]->codec->codec_type == codec_type)
  42                         ffs->si = i;
  43         if (ffs->si == -1)
  44                 goto failed;
  45         ffs->cc = ffs->fc->streams[ffs->si]->codec;
  46         avcodec_open(ffs->cc, avcodec_find_decoder(ffs->cc->codec_id));
  47         return ffs;
  48 failed:
  49         ffs_free(ffs);
  50         return NULL;
  51 }
  52
  53 void ffs_free(struct ffs *ffs)
  54 {
  55         if (ffs->swsc)
  56                 sws_freeContext(ffs->swsc);
  57         if (ffs->dst)
  58                 av_free(ffs->dst);
  59         if (ffs->tmp)
  60                 av_free(ffs->tmp);
  61         if (ffs->cc)
  62                 avcodec_close(ffs->cc);
  63         if (ffs->fc)
  64                 av_close_input_file(ffs->fc);
  65         free(ffs);
  66 }
  67
  68 static AVPacket *ffs_pkt(struct ffs *ffs)
  69 {
  70         AVPacket *pkt = &ffs->pkt;
  71         while (av_read_frame(ffs->fc, pkt) >= 0) {
  72                 ffs->seq_all++;
  73                 if (pkt->stream_index == ffs->si) {
  74                         ffs->seq_cur++;
  75                         ffs->seq++;
  76                         return pkt;
  77                 }
  78                 av_free_packet(pkt);
  79         }
  80         return NULL;
  81 }
  82
  83 static long ts_ms(void)
  84 {
  85         struct timeval tv;
  86         gettimeofday(&tv, NULL);
  87         return tv.tv_sec * 1000 + tv.tv_usec / 1000;
  88 }
  89
  90 static void wait(long ts, int vdelay)
  91 {
  92         int nts = ts_ms();
  93         if (ts + vdelay > nts)
  94                 usleep((ts + vdelay - nts) * 1000);
  95 }
  96
  97 void ffs_wait(struct ffs *ffs)
  98 {
  99         long ts = ts_ms();
 100         if (ts && ffs->ts) {
 101                 AVRational *r = &ffs->fc->streams[ffs->si]->time_base;
 102                 int vdelay = 1000 * r->num / r->den;
 103                 wait(ffs->ts, vdelay < 20 ? 20 : vdelay);
 104         }
 105         ffs->ts = ts_ms();
 106 }
 107
 108 long ffs_pos(struct ffs *ffs, int diff)
 109 {
 110         return (ffs->si << 28) | (ffs->seq + diff);
 111 }
 112
 113 void ffs_seek(struct ffs *ffs, long pos, int perframe)
 114 {
 115         long idx = pos >> 28;
 116         long seq = pos & 0x0fffffff;
 117         av_seek_frame(ffs->fc, idx, seq * perframe,
 118                         perframe == 1 ? AVSEEK_FLAG_FRAME : 0);
 119         ffs->seq = seq;
 120         ffs->seq_all = 0;
 121         ffs->seq_cur = 0;
 122         ffs->ts = 0;
 123 }
 124
 125 long ffs_seq(struct ffs *ffs, int all)
 126 {
 127         return all ? ffs->seq_all : ffs->seq_cur;
 128 }
 129
 130 void ffs_vinfo(struct ffs *ffs, int *w, int *h)
 131 {
 132         *h = ffs->cc->height;
 133         *w = ffs->cc->width;
 134 }
 135
 136 void ffs_ainfo(struct ffs *ffs, int *rate, int *bps, int *ch)
 137 {
 138         *rate = ffs->cc->sample_rate;
 139         *ch = ffs->cc->channels;
 140         *bps = 16;
 141 }
 142
 143 int ffs_vdec(struct ffs *ffs, char **buf)
 144 {
 145         AVCodecContext *vcc = ffs->cc;
 146         AVPacket *pkt = ffs_pkt(ffs);
 147         int fine = 0;
 148         if (!pkt)
 149                 return -1;
 150         avcodec_decode_video2(vcc, ffs->tmp, &fine, pkt);
 151         av_free_packet(pkt);
 152         if (fine && buf) {
 153                 sws_scale(ffs->swsc, ffs->tmp->data, ffs->tmp->linesize,
 154                           0, vcc->height, ffs->dst->data, ffs->dst->linesize);
 155                 *buf = (void *) ffs->dst->data[0];
 156                 return ffs->dst->linesize[0];
 157         }
 158         return 0;
 159 }
 160
 161 int ffs_adec(struct ffs *ffs, char *buf, int blen)
 162 {
 163         int rdec = 0;
 164         AVPacket tmppkt;
 165         AVPacket *pkt = ffs_pkt(ffs);
 166         if (!pkt)
 167                 return -1;
 168         tmppkt.size = pkt->size;
 169         tmppkt.data = pkt->data;
 170         while (tmppkt.size > 0) {
 171                 int size = blen - rdec;
 172                 int len = avcodec_decode_audio3(ffs->cc, (int16_t *) (buf + rdec),
 173                                                 &size, &tmppkt);
 174                 if (len < 0)
 175                         break;
 176                 tmppkt.size -= len;
 177                 tmppkt.data += len;
 178                 if (size > 0)
 179                         rdec += size;
 180         }
 181         av_free_packet(pkt);
 182         return rdec;
 183 }
 184
 185 void ffs_vsetup(struct ffs *ffs, float zoom, int pixfmt)
 186 {
 187         int h = ffs->cc->height;
 188         int w = ffs->cc->width;
 189         int fmt = ffs->cc->pix_fmt;
 190         uint8_t *buf = NULL;
 191         int n;
 192         ffs->swsc = sws_getContext(w, h, fmt, w * zoom, h * zoom,
 193                         pixfmt, SWS_FAST_BILINEAR | SWS_CPU_CAPS_MMX2,
 194                         NULL, NULL, NULL);
 195         ffs->dst = avcodec_alloc_frame();
 196         ffs->tmp = avcodec_alloc_frame();
 197         n = avpicture_get_size(pixfmt, w * zoom, h * zoom);
 198         buf = av_malloc(n * sizeof(uint8_t));
 199         avpicture_fill((AVPicture *) ffs->dst, buf, pixfmt, w * zoom, h * zoom);
 200 }
 201
 202 void ffs_globinit(void)
 203 {
 204         av_register_all();
 205 }