FFmpeg: libavformat/flic.c Source File

00001 /*
00002  * FLI/FLC Animation File Demuxer
00003  * Copyright (c) 2003 The ffmpeg Project
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00034 #include "libavutil/intreadwrite.h"
00035 #include "avformat.h"
00036 
00037 #define FLIC_FILE_MAGIC_1 0xAF11
00038 #define FLIC_FILE_MAGIC_2 0xAF12
00039 #define FLIC_FILE_MAGIC_3 0xAF44  /* Flic Type for Extended FLX Format which
00040                                      originated in Dave's Targa Animator (DTA) */
00041 #define FLIC_CHUNK_MAGIC_1 0xF1FA
00042 #define FLIC_CHUNK_MAGIC_2 0xF5FA
00043 #define FLIC_MC_SPEED 5  /* speed for Magic Carpet game FLIs */
00044 #define FLIC_DEFAULT_SPEED 5  /* for FLIs that have 0 speed */
00045 
00046 #define FLIC_HEADER_SIZE 128
00047 #define FLIC_PREAMBLE_SIZE 6
00048 
00049 typedef struct FlicDemuxContext {
00050     int video_stream_index;
00051     int frame_number;
00052 } FlicDemuxContext;
00053 
00054 static int flic_probe(AVProbeData *p)
00055 {
00056     int magic_number;
00057 
00058     if(p->buf_size < FLIC_HEADER_SIZE)
00059         return 0;
00060 
00061     magic_number = AV_RL16(&p->buf[4]);
00062     if ((magic_number != FLIC_FILE_MAGIC_1) &&
00063         (magic_number != FLIC_FILE_MAGIC_2) &&
00064         (magic_number != FLIC_FILE_MAGIC_3))
00065         return 0;
00066 
00067     if(AV_RL16(&p->buf[0x10]) != FLIC_CHUNK_MAGIC_1){
00068         if(AV_RL32(&p->buf[0x10]) > 2000)
00069             return 0;
00070     }
00071 
00072     if(   AV_RL16(&p->buf[0x08]) > 4096
00073        || AV_RL16(&p->buf[0x0A]) > 4096)
00074         return 0;
00075 
00076 
00077     return AVPROBE_SCORE_MAX;
00078 }
00079 
00080 static int flic_read_header(AVFormatContext *s,
00081                             AVFormatParameters *ap)
00082 {
00083     FlicDemuxContext *flic = s->priv_data;
00084     ByteIOContext *pb = s->pb;
00085     unsigned char header[FLIC_HEADER_SIZE];
00086     AVStream *st;
00087     int speed;
00088     int magic_number;
00089 
00090     flic->frame_number = 0;
00091 
00092     /* load the whole header and pull out the width and height */
00093     if (get_buffer(pb, header, FLIC_HEADER_SIZE) != FLIC_HEADER_SIZE)
00094         return AVERROR(EIO);
00095 
00096     magic_number = AV_RL16(&header[4]);
00097     speed = AV_RL32(&header[0x10]);
00098     if (speed == 0)
00099         speed = FLIC_DEFAULT_SPEED;
00100 
00101     /* initialize the decoder streams */
00102     st = av_new_stream(s, 0);
00103     if (!st)
00104         return AVERROR(ENOMEM);
00105     flic->video_stream_index = st->index;
00106     st->codec->codec_type = CODEC_TYPE_VIDEO;
00107     st->codec->codec_id = CODEC_ID_FLIC;
00108     st->codec->codec_tag = 0;  /* no fourcc */
00109     st->codec->width = AV_RL16(&header[0x08]);
00110     st->codec->height = AV_RL16(&header[0x0A]);
00111 
00112     if (!st->codec->width || !st->codec->height) {
00113         /* Ugly hack needed for the following sample: */
00114         /* http://samples.mplayerhq.hu/fli-flc/fli-bugs/specular.flc */
00115         av_log(s, AV_LOG_WARNING,
00116                "File with no specified width/height. Trying 640x480.\n");
00117         st->codec->width  = 640;
00118         st->codec->height = 480;
00119     }
00120 
00121     /* send over the whole 128-byte FLIC header */
00122     st->codec->extradata_size = FLIC_HEADER_SIZE;
00123     st->codec->extradata = av_malloc(FLIC_HEADER_SIZE);
00124     memcpy(st->codec->extradata, header, FLIC_HEADER_SIZE);
00125 
00126     /* Time to figure out the framerate: If there is a FLIC chunk magic
00127      * number at offset 0x10, assume this is from the Bullfrog game,
00128      * Magic Carpet. */
00129     if (AV_RL16(&header[0x10]) == FLIC_CHUNK_MAGIC_1) {
00130 
00131         av_set_pts_info(st, 64, FLIC_MC_SPEED, 70);
00132 
00133         /* rewind the stream since the first chunk is at offset 12 */
00134         url_fseek(pb, 12, SEEK_SET);
00135 
00136         /* send over abbreviated FLIC header chunk */
00137         av_free(st->codec->extradata);
00138         st->codec->extradata_size = 12;
00139         st->codec->extradata = av_malloc(12);
00140         memcpy(st->codec->extradata, header, 12);
00141 
00142     } else if (magic_number == FLIC_FILE_MAGIC_1) {
00143         av_set_pts_info(st, 64, speed, 70);
00144     } else if ((magic_number == FLIC_FILE_MAGIC_2) ||
00145                (magic_number == FLIC_FILE_MAGIC_3)) {
00146         av_set_pts_info(st, 64, speed, 1000);
00147     } else {
00148         av_log(s, AV_LOG_INFO, "Invalid or unsupported magic chunk in file\n");
00149         return AVERROR_INVALIDDATA;
00150     }
00151 
00152     return 0;
00153 }
00154 
00155 static int flic_read_packet(AVFormatContext *s,
00156                             AVPacket *pkt)
00157 {
00158     FlicDemuxContext *flic = s->priv_data;
00159     ByteIOContext *pb = s->pb;
00160     int packet_read = 0;
00161     unsigned int size;
00162     int magic;
00163     int ret = 0;
00164     unsigned char preamble[FLIC_PREAMBLE_SIZE];
00165 
00166     while (!packet_read) {
00167 
00168         if ((ret = get_buffer(pb, preamble, FLIC_PREAMBLE_SIZE)) !=
00169             FLIC_PREAMBLE_SIZE) {
00170             ret = AVERROR(EIO);
00171             break;
00172         }
00173 
00174         size = AV_RL32(&preamble[0]);
00175         magic = AV_RL16(&preamble[4]);
00176 
00177         if (((magic == FLIC_CHUNK_MAGIC_1) || (magic == FLIC_CHUNK_MAGIC_2)) && size > FLIC_PREAMBLE_SIZE) {
00178             if (av_new_packet(pkt, size)) {
00179                 ret = AVERROR(EIO);
00180                 break;
00181             }
00182             pkt->stream_index = flic->video_stream_index;
00183             pkt->pts = flic->frame_number++;
00184             pkt->pos = url_ftell(pb);
00185             memcpy(pkt->data, preamble, FLIC_PREAMBLE_SIZE);
00186             ret = get_buffer(pb, pkt->data + FLIC_PREAMBLE_SIZE,
00187                 size - FLIC_PREAMBLE_SIZE);
00188             if (ret != size - FLIC_PREAMBLE_SIZE) {
00189                 av_free_packet(pkt);
00190                 ret = AVERROR(EIO);
00191             }
00192             packet_read = 1;
00193         } else {
00194             /* not interested in this chunk */
00195             url_fseek(pb, size - 6, SEEK_CUR);
00196         }
00197     }
00198 
00199     return ret;
00200 }
00201 
00202 AVInputFormat flic_demuxer = {
00203     "flic",
00204     NULL_IF_CONFIG_SMALL("FLI/FLC/FLX animation format"),
00205     sizeof(FlicDemuxContext),
00206     flic_probe,
00207     flic_read_header,
00208     flic_read_packet,
00209 };