/*
  * YUV4MPEG format

  * Copyright (c) 2001, 2002, 2003 Fabrice Bellard

  *

  * 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

  */
 #include "avformat.h"
 
 #define Y4M_MAGIC "YUV4MPEG2"
 #define Y4M_FRAME_MAGIC "FRAME"
 #define Y4M_LINE_MAX 256
 

 struct frame_attributes {
     int interlaced_frame;
     int top_field_first;
 };
 

 #if CONFIG_YUV4MPEGPIPE_MUXER

 static int yuv4_generate_header(AVFormatContext *s, char* buf)

 {
     AVStream *st;
     int width, height;

     int raten, rated, aspectn, aspectd, n;

     char inter;

     const char *colorspace = "";

 
     st = s->streams[0];

     width = st->codec->width;
     height = st->codec->height;

     av_reduce(&raten, &rated, st->codec->time_base.den, st->codec->time_base.num, (1UL<<31)-1);

     aspectn = st->sample_aspect_ratio.num;
     aspectd = st->sample_aspect_ratio.den;

     if ( aspectn == 0 && aspectd == 1 ) aspectd = 0;  // 0:0 means unknown
 

     inter = 'p'; /* progressive is the default */

     if (st->codec->coded_frame && st->codec->coded_frame->interlaced_frame) {
         inter = st->codec->coded_frame->top_field_first ? 't' : 'b';

     }

     switch(st->codec->pix_fmt) {

     case PIX_FMT_GRAY8:
         colorspace = " Cmono";
         break;

     case PIX_FMT_YUV411P:
         colorspace = " C411 XYSCSS=411";
         break;
     case PIX_FMT_YUV420P:

         colorspace = (st->codec->codec_id == CODEC_ID_DVVIDEO)?" C420paldv XYSCSS=420PALDV":" C420mpeg2 XYSCSS=420MPEG2";

         break;
     case PIX_FMT_YUV422P:
         colorspace = " C422 XYSCSS=422";
         break;
     case PIX_FMT_YUV444P:
         colorspace = " C444 XYSCSS=444";
         break;
     }
 

     /* construct stream header, if this is the first frame */

     n = snprintf(buf, Y4M_LINE_MAX, "%s W%d H%d F%d:%d I%c A%d:%d%s\n",

                  Y4M_MAGIC,
                  width,
                  height,
                  raten, rated,

                  inter,
                  aspectn, aspectd,

                  colorspace);

     return n;

 }
 

 static int yuv4_write_packet(AVFormatContext *s, AVPacket *pkt)

 {

     AVStream *st = s->streams[pkt->stream_index];

     ByteIOContext *pb = s->pb;

     AVPicture *picture;

     int* first_pkt = s->priv_data;

     int width, height, h_chroma_shift, v_chroma_shift;

     int i, m;

     char buf2[Y4M_LINE_MAX+1];

     char buf1[20];

     uint8_t *ptr, *ptr1, *ptr2;

     picture = (AVPicture *)pkt->data;

     /* for the first packet we have to output the header as well */
     if (*first_pkt) {
         *first_pkt = 0;

         if (yuv4_generate_header(s, buf2) < 0) {
             av_log(s, AV_LOG_ERROR, "Error. YUV4MPEG stream header write failed.\n");

             return AVERROR(EIO);

         } else {
             put_buffer(pb, buf2, strlen(buf2));
         }

     }
 

     /* construct frame header */

     m = snprintf(buf1, sizeof(buf1), "%s\n", Y4M_FRAME_MAGIC);

     put_buffer(pb, buf1, strlen(buf1));
 

     width = st->codec->width;
     height = st->codec->height;

     ptr = picture->data[0];
     for(i=0;i<height;i++) {
         put_buffer(pb, ptr, width);
         ptr += picture->linesize[0];
     }
 

     if (st->codec->pix_fmt != PIX_FMT_GRAY8){

     // Adjust for smaller Cb and Cr planes

     avcodec_get_chroma_sub_sample(st->codec->pix_fmt, &h_chroma_shift, &v_chroma_shift);

     width >>= h_chroma_shift;
     height >>= v_chroma_shift;
 

     ptr1 = picture->data[1];
     ptr2 = picture->data[2];

     for(i=0;i<height;i++) {     /* Cb */

         put_buffer(pb, ptr1, width);
         ptr1 += picture->linesize[1];
     }

     for(i=0;i<height;i++) {     /* Cr */

         put_buffer(pb, ptr2, width);
             ptr2 += picture->linesize[2];
     }

     }

     put_flush_packet(pb);
     return 0;
 }
 

 static int yuv4_write_header(AVFormatContext *s)
 {
     int* first_pkt = s->priv_data;

     if (s->nb_streams != 1)

         return AVERROR(EIO);

     if (s->streams[0]->codec->pix_fmt == PIX_FMT_YUV411P) {

         av_log(s, AV_LOG_ERROR, "Warning: generating rarely used 4:1:1 YUV stream, some mjpegtools might not work.\n");

     }
     else if ((s->streams[0]->codec->pix_fmt != PIX_FMT_YUV420P) &&
              (s->streams[0]->codec->pix_fmt != PIX_FMT_YUV422P) &&
              (s->streams[0]->codec->pix_fmt != PIX_FMT_GRAY8) &&

              (s->streams[0]->codec->pix_fmt != PIX_FMT_YUV444P)) {

         av_log(s, AV_LOG_ERROR, "ERROR: yuv4mpeg only handles yuv444p, yuv422p, yuv420p, yuv411p and gray pixel formats. Use -pix_fmt to select one.\n");

         return AVERROR(EIO);

     }

     *first_pkt = 1;
     return 0;
 }
 

 AVOutputFormat yuv4mpegpipe_muxer = {

     "yuv4mpegpipe",

     NULL_IF_CONFIG_SMALL("YUV4MPEG pipe format"),

     "",

     "y4m",

     sizeof(int),

     CODEC_ID_NONE,
     CODEC_ID_RAWVIDEO,
     yuv4_write_header,
     yuv4_write_packet,
     .flags = AVFMT_RAWPICTURE,
 };

 #endif

 /* Header size increased to allow room for optional flags */
 #define MAX_YUV4_HEADER 80

 #define MAX_FRAME_HEADER 80

 
 static int yuv4_read_header(AVFormatContext *s, AVFormatParameters *ap)
 {

     char header[MAX_YUV4_HEADER+10];  // Include headroom for the longest option
     char *tokstart,*tokend,*header_end;

     int i;

     ByteIOContext *pb = s->pb;

     int width=-1, height=-1, raten=0, rated=0, aspectn=0, aspectd=0;

     enum PixelFormat pix_fmt=PIX_FMT_NONE,alt_pix_fmt=PIX_FMT_NONE;

     AVStream *st;

     struct frame_attributes *s1 = s->priv_data;

     for (i=0; i<MAX_YUV4_HEADER; i++) {
         header[i] = get_byte(pb);

         if (header[i] == '\n') {
             header[i+1] = 0x20;  // Add a space after last option. Makes parsing "444" vs "444alpha" easier.
             header[i+2] = 0;
             break;
         }

     }
     if (i == MAX_YUV4_HEADER) return -1;
     if (strncmp(header, Y4M_MAGIC, strlen(Y4M_MAGIC))) return -1;

     s1->interlaced_frame = 0;
     s1->top_field_first = 0;

     header_end = &header[i+1]; // Include space
     for(tokstart = &header[strlen(Y4M_MAGIC) + 1]; tokstart < header_end; tokstart++) {
         if (*tokstart==0x20) continue;
         switch (*tokstart++) {
         case 'W': // Width. Required.
             width = strtol(tokstart, &tokend, 10);
             tokstart=tokend;
             break;
         case 'H': // Height. Required.
             height = strtol(tokstart, &tokend, 10);
             tokstart=tokend;
             break;
         case 'C': // Color space
             if (strncmp("420jpeg",tokstart,7)==0)
                 pix_fmt = PIX_FMT_YUV420P;
             else if (strncmp("420mpeg2",tokstart,8)==0)
                 pix_fmt = PIX_FMT_YUV420P;
             else if (strncmp("420paldv", tokstart, 8)==0)
                 pix_fmt = PIX_FMT_YUV420P;
             else if (strncmp("411", tokstart, 3)==0)
                 pix_fmt = PIX_FMT_YUV411P;
             else if (strncmp("422", tokstart, 3)==0)
                 pix_fmt = PIX_FMT_YUV422P;
             else if (strncmp("444alpha", tokstart, 8)==0) {
                 av_log(s, AV_LOG_ERROR, "Cannot handle 4:4:4:4 YUV4MPEG stream.\n");
                 return -1;
             } else if (strncmp("444", tokstart, 3)==0)
                 pix_fmt = PIX_FMT_YUV444P;
             else if (strncmp("mono",tokstart, 4)==0) {

                 pix_fmt = PIX_FMT_GRAY8;

             } else {
                 av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains an unknown pixel format.\n");
                 return -1;
             }
             while(tokstart<header_end&&*tokstart!=0x20) tokstart++;
             break;
         case 'I': // Interlace type
             switch (*tokstart++){
             case '?':
                 break;
             case 'p':

                 s1->interlaced_frame=0;

                 break;
             case 't':

                 s1->interlaced_frame=1;
                 s1->top_field_first=1;

                 break;
             case 'b':

                 s1->interlaced_frame=1;
                 s1->top_field_first=0;

                 break;
             case 'm':
                 av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains mixed interlaced and non-interlaced frames.\n");
                 return -1;
             default:
                 av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
                 return -1;
             }
             break;
         case 'F': // Frame rate
             sscanf(tokstart,"%d:%d",&raten,&rated); // 0:0 if unknown
             while(tokstart<header_end&&*tokstart!=0x20) tokstart++;
             break;
         case 'A': // Pixel aspect
             sscanf(tokstart,"%d:%d",&aspectn,&aspectd); // 0:0 if unknown
             while(tokstart<header_end&&*tokstart!=0x20) tokstart++;
             break;
         case 'X': // Vendor extensions
             if (strncmp("YSCSS=",tokstart,6)==0) {
                 // Older nonstandard pixel format representation
                 tokstart+=6;
                 if (strncmp("420JPEG",tokstart,7)==0)
                     alt_pix_fmt=PIX_FMT_YUV420P;
                 else if (strncmp("420MPEG2",tokstart,8)==0)
                     alt_pix_fmt=PIX_FMT_YUV420P;
                 else if (strncmp("420PALDV",tokstart,8)==0)
                     alt_pix_fmt=PIX_FMT_YUV420P;
                 else if (strncmp("411",tokstart,3)==0)
                     alt_pix_fmt=PIX_FMT_YUV411P;
                 else if (strncmp("422",tokstart,3)==0)
                     alt_pix_fmt=PIX_FMT_YUV422P;
                 else if (strncmp("444",tokstart,3)==0)
                     alt_pix_fmt=PIX_FMT_YUV444P;
             }
             while(tokstart<header_end&&*tokstart!=0x20) tokstart++;
             break;
         }

     }

 
     if ((width == -1) || (height == -1)) {
         av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");

         return -1;

     }

     if (pix_fmt == PIX_FMT_NONE) {
         if (alt_pix_fmt == PIX_FMT_NONE)

             pix_fmt = PIX_FMT_YUV420P;
         else
             pix_fmt = alt_pix_fmt;
     }
 
     if (raten == 0 && rated == 0) {
         // Frame rate unknown
         raten = 25;
         rated = 1;
     }
 
     if (aspectn == 0 && aspectd == 0) {
         // Pixel aspect unknown
         aspectd = 1;
     }

     st = av_new_stream(s, 0);

     if(!st)

         return AVERROR(ENOMEM);

     st->codec->width = width;
     st->codec->height = height;

     av_reduce(&raten, &rated, raten, rated, (1UL<<31)-1);

     av_set_pts_info(st, 64, rated, raten);

     st->codec->pix_fmt = pix_fmt;
     st->codec->codec_type = CODEC_TYPE_VIDEO;
     st->codec->codec_id = CODEC_ID_RAWVIDEO;

     st->sample_aspect_ratio= (AVRational){aspectn, aspectd};

 
     return 0;
 }
 
 static int yuv4_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     int i;
     char header[MAX_FRAME_HEADER+1];

     int packet_size, width, height;

     AVStream *st = s->streams[0];

     struct frame_attributes *s1 = s->priv_data;

 
     for (i=0; i<MAX_FRAME_HEADER; i++) {

         header[i] = get_byte(s->pb);

         if (header[i] == '\n') {
             header[i+1] = 0;
             break;
         }

     }
     if (i == MAX_FRAME_HEADER) return -1;
     if (strncmp(header, Y4M_FRAME_MAGIC, strlen(Y4M_FRAME_MAGIC))) return -1;

     width = st->codec->width;
     height = st->codec->height;

     packet_size = avpicture_get_size(st->codec->pix_fmt, width, height);

     if (packet_size < 0)

         return -1;

     if (av_get_packet(s->pb, pkt, packet_size) != packet_size)

         return AVERROR(EIO);

     if (s->streams[0]->codec->coded_frame) {
         s->streams[0]->codec->coded_frame->interlaced_frame = s1->interlaced_frame;
         s->streams[0]->codec->coded_frame->top_field_first = s1->top_field_first;
     }
 

     pkt->stream_index = 0;

     return 0;

 }
 

 static int yuv4_probe(AVProbeData *pd)
 {
     /* check file header */
     if (strncmp(pd->buf, Y4M_MAGIC, sizeof(Y4M_MAGIC)-1)==0)
         return AVPROBE_SCORE_MAX;
     else
         return 0;
 }
 

 #if CONFIG_YUV4MPEGPIPE_DEMUXER

 AVInputFormat yuv4mpegpipe_demuxer = {

     "yuv4mpegpipe",

     NULL_IF_CONFIG_SMALL("YUV4MPEG pipe format"),

     sizeof(struct frame_attributes),

     yuv4_probe,

     yuv4_read_header,
     yuv4_read_packet,

     .extensions = "y4m"

 };

 #endif