warnings.c

   1 /*
   2  *  Copyright (c) 2013 The WebM project authors. All Rights Reserved.
   3  *
   4  *  Use of this source code is governed by a BSD-style license
   5  *  that can be found in the LICENSE file in the root of the source
   6  *  tree. An additional intellectual property rights grant can be found
   7  *  in the file PATENTS.  All contributing project authors may
   8  *  be found in the AUTHORS file in the root of the source tree.
   9  */
  10
  11 #include "./warnings.h"
  12
  13 #include <assert.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17
  18 #include "vpx/vpx_encoder.h"
  19
  20 #include "./tools_common.h"
  21 #include "./vpxenc.h"
  22
  23 static const char quantizer_warning_string[] =
  24     "Bad quantizer values. Quantizer values should not be equal, and should "
  25     "differ by at least 8.";
  26 static const char lag_in_frames_with_realtime[] =
  27     "Lag in frames is ignored when deadline is set to realtime.";
  28
  29 struct WarningListNode {
  30   const char *warning_string;
  31   struct WarningListNode *next_warning;
  32 };
  33
  34 struct WarningList {
  35   struct WarningListNode *warning_node;
  36 };
  37
  38 static void add_warning(const char *warning_string,
  39                         struct WarningList *warning_list) {
  40   struct WarningListNode **node = &warning_list->warning_node;
  41
  42   struct WarningListNode *new_node = malloc(sizeof(*new_node));
  43   if (new_node == NULL) {
  44     fatal("Unable to allocate warning node.");
  45   }
  46
  47   new_node->warning_string = warning_string;
  48   new_node->next_warning = NULL;
  49
  50   while (*node != NULL)
  51     node = &(*node)->next_warning;
  52
  53   *node = new_node;
  54 }
  55
  56 static void free_warning_list(struct WarningList *warning_list) {
  57   while (warning_list->warning_node != NULL) {
  58     struct WarningListNode *const node = warning_list->warning_node;
  59     warning_list->warning_node = node->next_warning;
  60     free(node);
  61   }
  62 }
  63
  64 static int continue_prompt(int num_warnings) {
  65   int c;
  66   fprintf(stderr,
  67           "%d encoder configuration warning(s). Continue? (y to continue) ",
  68           num_warnings);
  69   c = getchar();
  70   return c == 'y';
  71 }
  72
  73 static void check_quantizer(int min_q, int max_q,
  74                             struct WarningList *warning_list) {
  75   const int lossless = min_q == 0 && max_q == 0;
  76   if (!lossless && (min_q == max_q || abs(max_q - min_q) < 8))
  77     add_warning(quantizer_warning_string, warning_list);
  78 }
  79
  80 static void check_lag_in_frames_realtime_deadline(
  81     int lag_in_frames,
  82     int deadline,
  83     struct WarningList *warning_list) {
  84   if (deadline == VPX_DL_REALTIME && lag_in_frames != 0)
  85     add_warning(lag_in_frames_with_realtime, warning_list);
  86 }
  87
  88 void check_encoder_config(int disable_prompt,
  89                           const struct VpxEncoderConfig *global_config,
  90                           const struct vpx_codec_enc_cfg *stream_config) {
  91   int num_warnings = 0;
  92   struct WarningListNode *warning = NULL;
  93   struct WarningList warning_list = {0};
  94
  95   check_quantizer(stream_config->rc_min_quantizer,
  96                   stream_config->rc_max_quantizer,
  97                   &warning_list);
  98   check_lag_in_frames_realtime_deadline(stream_config->g_lag_in_frames,
  99                                         global_config->deadline,
 100                                         &warning_list);
 101   /* Count and print warnings. */
 102   for (warning = warning_list.warning_node;
 103        warning != NULL;
 104        warning = warning->next_warning,
 105        ++num_warnings) {
 106     warn(warning->warning_string);
 107   }
 108
 109   free_warning_list(&warning_list);
 110
 111   if (num_warnings) {
 112     if (!disable_prompt && !continue_prompt(num_warnings))
 113       exit(EXIT_FAILURE);
 114   }
 115 }