1 files changed, 90 insertions, 0 deletions

diff --git a/tools_common.c b/tools_common.c
index b1c35e815..2cd8a0704 100644
--- a/tools_common.c
+++ b/tools_common.c
@@ -46,6 +46,14 @@
     va_end(ap);                        \
   } while (0)
 
+#if CONFIG_ENCODERS
+/* Swallow warnings about unused results of fread/fwrite */
+static size_t wrap_fread(void *ptr, size_t size, size_t nmemb, FILE *stream) {
+  return fread(ptr, size, nmemb, stream);
+}
+#define fread wrap_fread
+#endif
+
 FILE *set_binary_mode(FILE *stream) {
   (void)stream;
 #if defined(_WIN32) || defined(__OS2__)
@@ -264,6 +272,88 @@ double sse_to_psnr(double samples, double peak, double sse) {
   }
 }
 
+#if CONFIG_ENCODERS
+int read_frame(struct VpxInputContext *input_ctx, vpx_image_t *img) {
+  FILE *f = input_ctx->file;
+  y4m_input *y4m = &input_ctx->y4m;
+  int shortread = 0;
+
+  if (input_ctx->file_type == FILE_TYPE_Y4M) {
+    if (y4m_input_fetch_frame(y4m, f, img) < 1) return 0;
+  } else {
+    shortread = read_yuv_frame(input_ctx, img);
+  }
+
+  return !shortread;
+}
+
+int file_is_y4m(const char detect[4]) {
+  if (memcmp(detect, "YUV4", 4) == 0) {
+    return 1;
+  }
+  return 0;
+}
+
+int fourcc_is_ivf(const char detect[4]) {
+  if (memcmp(detect, "DKIF", 4) == 0) {
+    return 1;
+  }
+  return 0;
+}
+
+void open_input_file(struct VpxInputContext *input) {
+  /* Parse certain options from the input file, if possible */
+  input->file = strcmp(input->filename, "-") ? fopen(input->filename, "rb")
+                                             : set_binary_mode(stdin);
+
+  if (!input->file) fatal("Failed to open input file");
+
+  if (!fseeko(input->file, 0, SEEK_END)) {
+    /* Input file is seekable. Figure out how long it is, so we can get
+     * progress info.
+     */
+    input->length = ftello(input->file);
+    rewind(input->file);
+  }
+
+  /* Default to 1:1 pixel aspect ratio. */
+  input->pixel_aspect_ratio.numerator = 1;
+  input->pixel_aspect_ratio.denominator = 1;
+
+  /* For RAW input sources, these bytes will applied on the first frame
+   *  in read_frame().
+   */
+  input->detect.buf_read = fread(input->detect.buf, 1, 4, input->file);
+  input->detect.position = 0;
+
+  if (input->detect.buf_read == 4 && file_is_y4m(input->detect.buf)) {
+    if (y4m_input_open(&input->y4m, input->file, input->detect.buf, 4,
+                       input->only_i420) >= 0) {
+      input->file_type = FILE_TYPE_Y4M;
+      input->width = input->y4m.pic_w;
+      input->height = input->y4m.pic_h;
+      input->pixel_aspect_ratio.numerator = input->y4m.par_n;
+      input->pixel_aspect_ratio.denominator = input->y4m.par_d;
+      input->framerate.numerator = input->y4m.fps_n;
+      input->framerate.denominator = input->y4m.fps_d;
+      input->fmt = input->y4m.vpx_fmt;
+      input->bit_depth = input->y4m.bit_depth;
+    } else {
+      fatal("Unsupported Y4M stream.");
+    }
+  } else if (input->detect.buf_read == 4 && fourcc_is_ivf(input->detect.buf)) {
+    fatal("IVF is not supported as input.");
+  } else {
+    input->file_type = FILE_TYPE_RAW;
+  }
+}
+
+void close_input_file(struct VpxInputContext *input) {
+  fclose(input->file);
+  if (input->file_type == FILE_TYPE_Y4M) y4m_input_close(&input->y4m);
+}
+#endif
+
 // TODO(debargha): Consolidate the functions below into a separate file.
 #if CONFIG_VP9_HIGHBITDEPTH
 static void highbd_img_upshift(vpx_image_t *dst, vpx_image_t *src,