simplify AVFormatParameters NULL checks

Originally committed as revision 5146 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/audio.c

@@ -217,7 +217,7 @@ static int audio_read_header(AVFormatContext *s1, AVFormatParameters *ap)
     AVStream *st;
     int ret;
 
-    if (!ap || ap->sample_rate <= 0 || ap->channels <= 0)
+    if (ap->sample_rate <= 0 || ap->channels <= 0)
         return -1;
 
     st = av_new_stream(s1, 0);

libavformat/grab.c

@@ -68,7 +68,7 @@ static int grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
     const char *video_device;
     int j;
 
-    if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0)
+    if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0)
         return -1;
 
     width = ap->width;

libavformat/grab_bktr.c

@@ -245,7 +245,7 @@ static int grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
     int format = -1;
     const char *video_device;
 
-    if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0)
+    if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0)
         return -1;
 
     width = ap->width;

libavformat/img.c

@@ -120,7 +120,7 @@ static int img_read_header(AVFormatContext *s1, AVFormatParameters *ap)
         return -ENOMEM;
     }
 
-    if (ap && ap->image_format)
+    if (ap->image_format)
         s->img_fmt = ap->image_format;
 
     pstrcpy(s->path, sizeof(s->path), s1->filename);
@@ -133,7 +133,7 @@ static int img_read_header(AVFormatContext *s1, AVFormatParameters *ap)
     else
         s->is_pipe = 1;
 
-    if (!ap || !ap->time_base.num) {
+    if (!ap->time_base.num) {
         st->codec->time_base= (AVRational){1,25};
     } else {
         st->codec->time_base= ap->time_base;
@@ -255,7 +255,7 @@ static int img_set_parameters(AVFormatContext *s, AVFormatParameters *ap)
     int i;
 
     /* find output image format */
-    if (ap && ap->image_format) {
+    if (ap->image_format) {
         img_fmt = ap->image_format;
     } else {
         img_fmt = guess_image_format(s->filename);

libavformat/img2.c

@@ -187,13 +187,13 @@ static int img_read_header(AVFormatContext *s1, AVFormatParameters *ap)
         st->need_parsing= 1;
     }
 
-    if (!ap || !ap->time_base.num) {
+    if (!ap->time_base.num) {
         av_set_pts_info(st, 60, 1, 25);
     } else {
         av_set_pts_info(st, 60, ap->time_base.num, ap->time_base.den);
     }
 
-    if(ap && ap->width && ap->height){
+    if(ap->width && ap->height){
         st->codec->width = ap->width;
         st->codec->height= ap->height;
     }

libavformat/raw.c

@@ -48,7 +48,7 @@ static int raw_read_header(AVFormatContext *s, AVFormatParameters *ap)
     st = av_new_stream(s, 0);
     if (!st)
         return AVERROR_NOMEM;
-    if (ap) {
+
         id = s->iformat->value;
         if (id == CODEC_ID_RAWVIDEO) {
             st->codec->codec_type = CODEC_TYPE_VIDEO;
@@ -74,9 +74,6 @@ static int raw_read_header(AVFormatContext *s, AVFormatParameters *ap)
         default:
             return -1;
         }
-    } else {
-        return -1;
-    }
     return 0;
 }
 
@@ -289,7 +286,7 @@ static int video_read_header(AVFormatContext *s,
 
     /* for mjpeg, specify frame rate */
     /* for mpeg4 specify it too (most mpeg4 streams dont have the fixed_vop_rate set ...)*/
-    if (ap && ap->time_base.num) {
+    if (ap->time_base.num) {
         av_set_pts_info(st, 64, ap->time_base.num, ap->time_base.den);
     } else if ( st->codec->codec_id == CODEC_ID_MJPEG ||
                 st->codec->codec_id == CODEC_ID_MPEG4 ||

libavformat/rtsp.c

@@ -994,7 +994,7 @@ static int rtsp_read_header(AVFormatContext *s,
     rt->state = RTSP_STATE_IDLE;
     rt->seek_timestamp = 0; /* default is to start stream at position
                                zero */
-    if (ap && ap->initial_pause) {
+    if (ap->initial_pause) {
         /* do not start immediately */
     } else {
         if (rtsp_read_play(s) < 0) {

libavformat/utils.c

@@ -465,6 +465,12 @@ int av_open_input_stream(AVFormatContext **ic_ptr,
 {
     int err;
     AVFormatContext *ic;
+    AVFormatParameters default_ap;
+
+    if(!ap){
+        ap=&default_ap;
+        memset(ap, 0, sizeof(default_ap));
+    }
 
     ic = av_alloc_format_context();
     if (!ic) {

libavformat/v4l2.c

@@ -384,7 +384,7 @@ static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
     uint32_t desired_format, capabilities;
     const char *video_device;
 
-    if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
+    if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
         av_log(s1, AV_LOG_ERROR, "Missing/Wrong parameters\n");
 
         return -1;