RoQ encoder: support different integer framerates

Even though the most common framerate for RoQ is 30fps,
the format supports other framerates too.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/roqvideoenc.c

@@ -963,7 +963,7 @@ static av_cold int roq_encode_init(AVCodecContext *avctx)
     enc->framesSinceKeyframe = 0;
     if ((avctx->width & 0xf) || (avctx->height & 0xf)) {
         av_log(avctx, AV_LOG_ERROR, "Dimensions must be divisible by 16\n");
-        return -1;
+        return AVERROR(EINVAL);
     }
 
     if (((avctx->width)&(avctx->width-1))||((avctx->height)&(avctx->height-1)))
@@ -1097,7 +1097,6 @@ AVCodec ff_roq_encoder = {
     .init                 = roq_encode_init,
     .encode2              = roq_encode_frame,
     .close                = roq_encode_end,
-    .supported_framerates = (const AVRational[]){ {30,1}, {0,0} },
     .pix_fmts             = (const enum AVPixelFormat[]){ AV_PIX_FMT_YUV444P,
                                                         AV_PIX_FMT_NONE },
     .priv_class     = &roq_class,

libavformat/idroqenc.c

@@ -25,9 +25,35 @@
 
 static int roq_write_header(struct AVFormatContext *s)
 {
-    static const uint8_t header[] = {
-        0x84, 0x10, 0xFF, 0xFF, 0xFF, 0xFF, 0x1E, 0x00
+    uint8_t header[] = {
+        0x84, 0x10, 0xFF, 0xFF, 0xFF, 0xFF, /* fps: */ 0x1E, 0x00
     };
+    int n;
+    AVCodecContext *avctx;
+
+// set the actual fps
+    for(n=0;n<s->nb_streams;n++) {
+        if ((avctx=s->streams[n]->codec)->codec_type == AVMEDIA_TYPE_VIDEO) {
+            unsigned int fps;
+
+            if (avctx->time_base.num != 1) {
+                av_log(avctx, AV_LOG_ERROR, "Frame rate must be integer\n");
+                return AVERROR(EINVAL);
+            }
+
+            if ((fps=avctx->time_base.den) > 255) {
+                av_log(avctx, AV_LOG_ERROR, "Frame rate may not exceed 255fps\n");
+                return AVERROR(EINVAL);
+            }
+
+            if (fps != 30) {
+                av_log(avctx, AV_LOG_WARNING, "For vintage compatibility fps must be 30\n");
+            }
+
+            header[6] = fps;
+            break;
+        }
+    }
 
     avio_write(s->pb, header, 8);
     avio_flush(s->pb);

tests/fate/video.mak

@@ -139,7 +139,7 @@ FATE_VIDEO-$(call DEMDEC, IDCIN, IDCIN) += fate-id-cin-video
 fate-id-cin-video: CMD = framecrc -i $(TARGET_SAMPLES)/idcin/idlog-2MB.cin -pix_fmt rgb24
 
 FATE_VIDEO-$(call ENCDEC, ROQ PGMYUV, ROQ IMAGE2) += fate-idroq-video-encode
-fate-idroq-video-encode: CMD = md5 -f image2 -vcodec pgmyuv -i $(TARGET_SAMPLES)/ffmpeg-synthetic/vsynth1/%02d.pgm -sws_flags +bitexact -vf pad=512:512:80:112 -f roq -t 0.2
+fate-idroq-video-encode: CMD = md5 -f image2 -vcodec pgmyuv -i $(TARGET_SAMPLES)/ffmpeg-synthetic/vsynth1/%02d.pgm -r 30 -sws_flags +bitexact -vf pad=512:512:80:112 -f roq -t 0.2
 
 FATE_IFF-$(CONFIG_IFF_BYTERUN1_DECODER) += fate-iff-byterun1
 fate-iff-byterun1: CMD = framecrc -i $(TARGET_SAMPLES)/iff/ASH.LBM -pix_fmt rgb24