The Tor Browser: media/libvpx/vpx/src/svc_encodeframe.c@ac0c01689b40 (annotated)

media/libvpx/vpx/src/svc_encodeframe.c@ac0c01689b40 (annotated)

media/libvpx/vpx/src/svc_encodeframe.c

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /*
  *  Copyright (c) 2013 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 /**
  * @file
  * VP9 SVC encoding support via libvpx
  */
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #define VPX_DISABLE_CTRL_TYPECHECKS 1
 #define VPX_CODEC_DISABLE_COMPAT 1
 #include "vpx/svc_context.h"
 #include "vpx/vp8cx.h"
 #include "vpx/vpx_encoder.h"
 #ifdef __MINGW32__
 #define strtok_r strtok_s
 #ifndef MINGW_HAS_SECURE_API
 // proto from /usr/x86_64-w64-mingw32/include/sec_api/string_s.h
 _CRTIMP char *__cdecl strtok_s(char *str, const char *delim, char **context);
 #endif  /* MINGW_HAS_SECURE_API */
 #endif  /* __MINGW32__ */
 #ifdef _MSC_VER
 #define strdup _strdup
 #define strtok_r strtok_s
 #endif
 #define SVC_REFERENCE_FRAMES 8
 #define SUPERFRAME_SLOTS (8)
 #define SUPERFRAME_BUFFER_SIZE (SUPERFRAME_SLOTS * sizeof(uint32_t) + 2)
 #define OPTION_BUFFER_SIZE 256
 static const char *DEFAULT_QUANTIZER_VALUES = "60,53,39,33,27";
 static const char *DEFAULT_SCALE_FACTORS = "4/16,5/16,7/16,11/16,16/16";
 typedef struct SvcInternal {
   char options[OPTION_BUFFER_SIZE];        // set by vpx_svc_set_options
   char quantizers[OPTION_BUFFER_SIZE];     // set by vpx_svc_set_quantizers
   char scale_factors[OPTION_BUFFER_SIZE];  // set by vpx_svc_set_scale_factors
   // values extracted from option, quantizers
   int scaling_factor_num[VPX_SS_MAX_LAYERS];
   int scaling_factor_den[VPX_SS_MAX_LAYERS];
   int quantizer[VPX_SS_MAX_LAYERS];
   // accumulated statistics
   double psnr_in_layer[VPX_SS_MAX_LAYERS];
   uint32_t bytes_in_layer[VPX_SS_MAX_LAYERS];
   // codec encoding values
   int width;    // width of highest layer
   int height;   // height of highest layer
   int kf_dist;  // distance between keyframes
   // state variables
   int encode_frame_count;
   int frame_within_gop;
   vpx_enc_frame_flags_t enc_frame_flags;
   int layers;
   int layer;
   int is_keyframe;
   size_t frame_size;
   size_t buffer_size;
   void *buffer;
   char message_buffer[2048];
   vpx_codec_ctx_t *codec_ctx;
 } SvcInternal;
 // Superframe is used to generate an index of individual frames (i.e., layers)
 struct Superframe {
   int count;
   uint32_t sizes[SUPERFRAME_SLOTS];
   uint32_t magnitude;
   uint8_t buffer[SUPERFRAME_BUFFER_SIZE];
   size_t index_size;
 };
 // One encoded frame layer
 struct LayerData {
   void *buf;    // compressed data buffer
   size_t size;  // length of compressed data
   struct LayerData *next;
 };
 // create LayerData from encoder output
 static struct LayerData *ld_create(void *buf, size_t size) {
   struct LayerData *const layer_data = malloc(sizeof(*layer_data));
   if (layer_data == NULL) {
     return NULL;
   }
   layer_data->buf = malloc(size);
   if (layer_data->buf == NULL) {
     free(layer_data);
     return NULL;
   }
   memcpy(layer_data->buf, buf, size);
   layer_data->size = size;
   return layer_data;
 }
 // free LayerData
 static void ld_free(struct LayerData *layer_data) {
   if (layer_data) {
     if (layer_data->buf) {
       free(layer_data->buf);
       layer_data->buf = NULL;
     }
     free(layer_data);
   }
 }
 // add layer data to list
 static void ld_list_add(struct LayerData **list, struct LayerData *layer_data) {
   struct LayerData **p = list;
   while (*p != NULL) p = &(*p)->next;
   *p = layer_data;
   layer_data->next = NULL;
 }
 // get accumulated size of layer data
 static size_t ld_list_get_buffer_size(struct LayerData *list) {
   struct LayerData *p;
   size_t size = 0;
   for (p = list; p != NULL; p = p->next) {
     size += p->size;
   }
   return size;
 }
 // copy layer data to buffer
 static void ld_list_copy_to_buffer(struct LayerData *list, uint8_t *buffer) {
   struct LayerData *p;
   for (p = list; p != NULL; p = p->next) {
     buffer[0] = 1;
     memcpy(buffer, p->buf, p->size);
     buffer += p->size;
   }
 }
 // free layer data list
 static void ld_list_free(struct LayerData *list) {
   struct LayerData *p = list;
   while (p) {
     list = list->next;
     ld_free(p);
     p = list;
   }
 }
 static void sf_create_index(struct Superframe *sf) {
   uint8_t marker = 0xc0;
   int i;
   uint32_t mag, mask;
   uint8_t *bufp;
   if (sf->count == 0 || sf->count >= 8) return;
   // Add the number of frames to the marker byte
   marker |= sf->count - 1;
   // Choose the magnitude
   for (mag = 0, mask = 0xff; mag < 4; ++mag) {
     if (sf->magnitude < mask) break;
     mask <<= 8;
     mask |= 0xff;
   }
   marker |= mag << 3;
   // Write the index
   sf->index_size = 2 + (mag + 1) * sf->count;
   bufp = sf->buffer;
   *bufp++ = marker;
   for (i = 0; i < sf->count; ++i) {
     int this_sz = sf->sizes[i];
     uint32_t j;
     for (j = 0; j <= mag; ++j) {
       *bufp++ = this_sz & 0xff;
       this_sz >>= 8;
     }
   }
   *bufp++ = marker;
 }
 static SvcInternal *get_svc_internal(SvcContext *svc_ctx) {
   if (svc_ctx == NULL) return NULL;
   if (svc_ctx->internal == NULL) {
     SvcInternal *const si = malloc(sizeof(*si));
     if (si != NULL) {
       memset(si, 0, sizeof(*si));
     }
     svc_ctx->internal = si;
   }
   return svc_ctx->internal;
 }
 static const SvcInternal *get_const_svc_internal(const SvcContext *svc_ctx) {
   if (svc_ctx == NULL) return NULL;
   return svc_ctx->internal;
 }
 static void svc_log_reset(SvcContext *svc_ctx) {
   SvcInternal *const si = (SvcInternal *)svc_ctx->internal;
   si->message_buffer[0] = '\0';
 }
 static int svc_log(SvcContext *svc_ctx, int level, const char *fmt, ...) {
   char buf[512];
   int retval = 0;
   va_list ap;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (level > svc_ctx->log_level) {
     return retval;
   }
   va_start(ap, fmt);
   retval = vsnprintf(buf, sizeof(buf), fmt, ap);
   va_end(ap);
   if (svc_ctx->log_print) {
     printf("%s", buf);
   } else {
     strncat(si->message_buffer, buf,
             sizeof(si->message_buffer) - strlen(si->message_buffer) - 1);
   }
   if (level == SVC_LOG_ERROR) {
     si->codec_ctx->err_detail = si->message_buffer;
   }
   return retval;
 }
 static vpx_codec_err_t set_option_encoding_mode(SvcContext *svc_ctx,
                                                 const char *value_str) {
   if (strcmp(value_str, "i") == 0) {
     svc_ctx->encoding_mode = INTER_LAYER_PREDICTION_I;
   } else if (strcmp(value_str, "alt-ip") == 0) {
     svc_ctx->encoding_mode = ALT_INTER_LAYER_PREDICTION_IP;
   } else if (strcmp(value_str, "ip") == 0) {
     svc_ctx->encoding_mode = INTER_LAYER_PREDICTION_IP;
   } else if (strcmp(value_str, "gf") == 0) {
     svc_ctx->encoding_mode = USE_GOLDEN_FRAME;
   } else {
     svc_log(svc_ctx, SVC_LOG_ERROR, "invalid encoding mode: %s", value_str);
     return VPX_CODEC_INVALID_PARAM;
   }
   return VPX_CODEC_OK;
 }
 static vpx_codec_err_t parse_quantizer_values(SvcContext *svc_ctx,
                                               const char *quantizer_values) {
   char *input_string;
   char *token;
   const char *delim = ",";
   char *save_ptr;
   int found = 0;
   int i, q;
   int res = VPX_CODEC_OK;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (quantizer_values == NULL || strlen(quantizer_values) == 0) {
     input_string = strdup(DEFAULT_QUANTIZER_VALUES);
   } else {
     input_string = strdup(quantizer_values);
   }
   token = strtok_r(input_string, delim, &save_ptr);
   for (i = 0; i < svc_ctx->spatial_layers; ++i) {
     if (token != NULL) {
       q = atoi(token);
       if (q <= 0 || q > 100) {
         svc_log(svc_ctx, SVC_LOG_ERROR,
                 "svc-quantizer-values: invalid value %s\n", token);
         res = VPX_CODEC_INVALID_PARAM;
         break;
       }
       token = strtok_r(NULL, delim, &save_ptr);
       found = i + 1;
     } else {
       q = 0;
     }
     si->quantizer[i + VPX_SS_MAX_LAYERS - svc_ctx->spatial_layers] = q;
   }
   if (res == VPX_CODEC_OK && found != svc_ctx->spatial_layers) {
     svc_log(svc_ctx, SVC_LOG_ERROR,
             "svc: quantizers: %d values required, but only %d specified\n",
             svc_ctx->spatial_layers, found);
     res = VPX_CODEC_INVALID_PARAM;
   }
   free(input_string);
   return res;
 }
 static void log_invalid_scale_factor(SvcContext *svc_ctx, const char *value) {
   svc_log(svc_ctx, SVC_LOG_ERROR, "svc scale-factors: invalid value %s\n",
           value);
 }
 static vpx_codec_err_t parse_scale_factors(SvcContext *svc_ctx,
                                            const char *scale_factors) {
   char *input_string;
   char *token;
   const char *delim = ",";
   char *save_ptr;
   int found = 0;
   int i;
   int64_t num, den;
   int res = VPX_CODEC_OK;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (scale_factors == NULL || strlen(scale_factors) == 0) {
     input_string = strdup(DEFAULT_SCALE_FACTORS);
   } else {
     input_string = strdup(scale_factors);
   }
   token = strtok_r(input_string, delim, &save_ptr);
   for (i = 0; i < svc_ctx->spatial_layers; ++i) {
     num = den = 0;
     if (token != NULL) {
       num = strtol(token, &token, 10);
       if (num <= 0) {
         log_invalid_scale_factor(svc_ctx, token);
         res = VPX_CODEC_INVALID_PARAM;
         break;
       }
       if (*token++ != '/') {
         log_invalid_scale_factor(svc_ctx, token);
         res = VPX_CODEC_INVALID_PARAM;
         break;
       }
       den = strtol(token, &token, 10);
       if (den <= 0) {
         log_invalid_scale_factor(svc_ctx, token);
         res = VPX_CODEC_INVALID_PARAM;
         break;
       }
       token = strtok_r(NULL, delim, &save_ptr);
       found = i + 1;
     }
     si->scaling_factor_num[i + VPX_SS_MAX_LAYERS - svc_ctx->spatial_layers] =
         (int)num;
     si->scaling_factor_den[i + VPX_SS_MAX_LAYERS - svc_ctx->spatial_layers] =
         (int)den;
   }
   if (res == VPX_CODEC_OK && found != svc_ctx->spatial_layers) {
     svc_log(svc_ctx, SVC_LOG_ERROR,
             "svc: scale-factors: %d values required, but only %d specified\n",
             svc_ctx->spatial_layers, found);
     res = VPX_CODEC_INVALID_PARAM;
   }
   free(input_string);
   return res;
 }
 /**
  * Parse SVC encoding options
  * Format: encoding-mode=<svc_mode>,layers=<layer_count>
  *         scale-factors=<n1>/<d1>,<n2>/<d2>,...
  *         quantizers=<q1>,<q2>,...
  * svc_mode = [i|ip|alt_ip|gf]
  */
 static vpx_codec_err_t parse_options(SvcContext *svc_ctx, const char *options) {
   char *input_string;
   char *option_name;
   char *option_value;
   char *input_ptr;
   int res = VPX_CODEC_OK;
   if (options == NULL) return VPX_CODEC_OK;
   input_string = strdup(options);
   // parse option name
   option_name = strtok_r(input_string, "=", &input_ptr);
   while (option_name != NULL) {
     // parse option value
     option_value = strtok_r(NULL, " ", &input_ptr);
     if (option_value == NULL) {
       svc_log(svc_ctx, SVC_LOG_ERROR, "option missing value: %s\n",
               option_name);
       res = VPX_CODEC_INVALID_PARAM;
       break;
     }
     if (strcmp("encoding-mode", option_name) == 0) {
       res = set_option_encoding_mode(svc_ctx, option_value);
       if (res != VPX_CODEC_OK) break;
     } else if (strcmp("layers", option_name) == 0) {
       svc_ctx->spatial_layers = atoi(option_value);
     } else if (strcmp("scale-factors", option_name) == 0) {
       res = parse_scale_factors(svc_ctx, option_value);
       if (res != VPX_CODEC_OK) break;
     } else if (strcmp("quantizers", option_name) == 0) {
       res = parse_quantizer_values(svc_ctx, option_value);
       if (res != VPX_CODEC_OK) break;
     } else {
       svc_log(svc_ctx, SVC_LOG_ERROR, "invalid option: %s\n", option_name);
       res = VPX_CODEC_INVALID_PARAM;
       break;
     }
     option_name = strtok_r(NULL, "=", &input_ptr);
   }
   free(input_string);
   return res;
 }
 vpx_codec_err_t vpx_svc_set_options(SvcContext *svc_ctx, const char *options) {
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || options == NULL || si == NULL) {
     return VPX_CODEC_INVALID_PARAM;
   }
   strncpy(si->options, options, sizeof(si->options));
   si->options[sizeof(si->options) - 1] = '\0';
   return VPX_CODEC_OK;
 }
 vpx_codec_err_t vpx_svc_set_quantizers(SvcContext *svc_ctx,
                                        const char *quantizers) {
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || quantizers == NULL || si == NULL) {
     return VPX_CODEC_INVALID_PARAM;
   }
   strncpy(si->quantizers, quantizers, sizeof(si->quantizers));
   si->quantizers[sizeof(si->quantizers) - 1] = '\0';
   return VPX_CODEC_OK;
 }
 vpx_codec_err_t vpx_svc_set_scale_factors(SvcContext *svc_ctx,
                                           const char *scale_factors) {
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || scale_factors == NULL || si == NULL) {
     return VPX_CODEC_INVALID_PARAM;
   }
   strncpy(si->scale_factors, scale_factors, sizeof(si->scale_factors));
   si->scale_factors[sizeof(si->scale_factors) - 1] = '\0';
   return VPX_CODEC_OK;
 }
 vpx_codec_err_t vpx_svc_init(SvcContext *svc_ctx, vpx_codec_ctx_t *codec_ctx,
                              vpx_codec_iface_t *iface,
                              vpx_codec_enc_cfg_t *enc_cfg) {
   int max_intra_size_pct;
   vpx_codec_err_t res;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || codec_ctx == NULL || iface == NULL ||
       enc_cfg == NULL) {
     return VPX_CODEC_INVALID_PARAM;
   }
   if (si == NULL) return VPX_CODEC_MEM_ERROR;
   si->codec_ctx = codec_ctx;
   si->width = enc_cfg->g_w;
   si->height = enc_cfg->g_h;
   if (enc_cfg->kf_max_dist < 2) {
     svc_log(svc_ctx, SVC_LOG_ERROR, "key frame distance too small: %d\n",
             enc_cfg->kf_max_dist);
     return VPX_CODEC_INVALID_PARAM;
   }
   si->kf_dist = enc_cfg->kf_max_dist;
   if (svc_ctx->spatial_layers == 0)
     svc_ctx->spatial_layers = VPX_SS_DEFAULT_LAYERS;
   if (svc_ctx->spatial_layers < 1 ||
       svc_ctx->spatial_layers > VPX_SS_MAX_LAYERS) {
     svc_log(svc_ctx, SVC_LOG_ERROR, "spatial layers: invalid value: %d\n",
             svc_ctx->spatial_layers);
     return VPX_CODEC_INVALID_PARAM;
   }
   // use SvcInternal value for number of layers to enable forcing single layer
   // for first frame
   si->layers = svc_ctx->spatial_layers;
   res = parse_quantizer_values(svc_ctx, si->quantizers);
   if (res != VPX_CODEC_OK) return res;
   res = parse_scale_factors(svc_ctx, si->scale_factors);
   if (res != VPX_CODEC_OK) return res;
   // parse aggregate command line options
   res = parse_options(svc_ctx, si->options);
   if (res != VPX_CODEC_OK) return res;
   // modify encoder configuration
   enc_cfg->ss_number_layers = si->layers;
   enc_cfg->kf_mode = VPX_KF_DISABLED;
   enc_cfg->g_pass = VPX_RC_ONE_PASS;
   // Lag in frames not currently supported
   enc_cfg->g_lag_in_frames = 0;
   // TODO(ivanmaltz): determine if these values need to be set explicitly for
   // svc, or if the normal default/override mechanism can be used
   enc_cfg->rc_dropframe_thresh = 0;
   enc_cfg->rc_end_usage = VPX_CBR;
   enc_cfg->rc_resize_allowed = 0;
   enc_cfg->rc_min_quantizer = 33;
   enc_cfg->rc_max_quantizer = 33;
   enc_cfg->rc_undershoot_pct = 100;
   enc_cfg->rc_overshoot_pct = 15;
   enc_cfg->rc_buf_initial_sz = 500;
   enc_cfg->rc_buf_optimal_sz = 600;
   enc_cfg->rc_buf_sz = 1000;
   enc_cfg->g_error_resilient = 1;
   // Initialize codec
   res = vpx_codec_enc_init(codec_ctx, iface, enc_cfg, VPX_CODEC_USE_PSNR);
   if (res != VPX_CODEC_OK) {
     svc_log(svc_ctx, SVC_LOG_ERROR, "svc_enc_init error\n");
     return res;
   }
   vpx_codec_control(codec_ctx, VP9E_SET_SVC, 1);
   vpx_codec_control(codec_ctx, VP8E_SET_CPUUSED, 1);
   vpx_codec_control(codec_ctx, VP8E_SET_STATIC_THRESHOLD, 1);
   vpx_codec_control(codec_ctx, VP8E_SET_NOISE_SENSITIVITY, 1);
   vpx_codec_control(codec_ctx, VP8E_SET_TOKEN_PARTITIONS, 1);
   max_intra_size_pct =
       (int)(((double)enc_cfg->rc_buf_optimal_sz * 0.5) *
             ((double)enc_cfg->g_timebase.den / enc_cfg->g_timebase.num) / 10.0);
   vpx_codec_control(codec_ctx, VP8E_SET_MAX_INTRA_BITRATE_PCT,
                     max_intra_size_pct);
   return VPX_CODEC_OK;
 }
 // SVC Algorithm flags - these get mapped to VP8_EFLAG_* defined in vp8cx.h
 // encoder should reference the last frame
 #define USE_LAST (1 << 0)
 // encoder should reference the alt ref frame
 #define USE_ARF (1 << 1)
 // encoder should reference the golden frame
 #define USE_GF (1 << 2)
 // encoder should copy current frame to the last frame buffer
 #define UPDATE_LAST (1 << 3)
 // encoder should copy current frame to the alt ref frame buffer
 #define UPDATE_ARF (1 << 4)
 // encoder should copy current frame to the golden frame
 #define UPDATE_GF (1 << 5)
 static int map_vp8_flags(int svc_flags) {
   int flags = 0;
   if (!(svc_flags & USE_LAST)) flags |= VP8_EFLAG_NO_REF_LAST;
   if (!(svc_flags & USE_ARF)) flags |= VP8_EFLAG_NO_REF_ARF;
   if (!(svc_flags & USE_GF)) flags |= VP8_EFLAG_NO_REF_GF;
   if (svc_flags & UPDATE_LAST) {
     // last is updated automatically
   } else {
     flags |= VP8_EFLAG_NO_UPD_LAST;
   }
   if (svc_flags & UPDATE_ARF) {
     flags |= VP8_EFLAG_FORCE_ARF;
   } else {
     flags |= VP8_EFLAG_NO_UPD_ARF;
   }
   if (svc_flags & UPDATE_GF) {
     flags |= VP8_EFLAG_FORCE_GF;
   } else {
     flags |= VP8_EFLAG_NO_UPD_GF;
   }
   return flags;
 }
 /**
  * Helper to check if the current frame is the first, full resolution dummy.
  */
 static int vpx_svc_dummy_frame(SvcContext *svc_ctx) {
   SvcInternal *const si = get_svc_internal(svc_ctx);
   return svc_ctx->first_frame_full_size == 1 && si->encode_frame_count == 0;
 }
 static void calculate_enc_frame_flags(SvcContext *svc_ctx) {
   vpx_enc_frame_flags_t flags = VPX_EFLAG_FORCE_KF;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   const int is_keyframe = (si->frame_within_gop == 0);
   // keyframe layer zero is identical for all modes
   if ((is_keyframe && si->layer == 0) || vpx_svc_dummy_frame(svc_ctx)) {
     si->enc_frame_flags = VPX_EFLAG_FORCE_KF;
     return;
   }
   switch (svc_ctx->encoding_mode) {
     case ALT_INTER_LAYER_PREDICTION_IP:
       if (si->layer == 0) {
         flags = map_vp8_flags(USE_LAST | UPDATE_LAST);
       } else if (is_keyframe) {
         if (si->layer == si->layers - 1) {
           flags = map_vp8_flags(USE_ARF | UPDATE_LAST);
         } else {
           flags = map_vp8_flags(USE_ARF | UPDATE_LAST | UPDATE_GF);
         }
       } else {
         flags = map_vp8_flags(USE_LAST | USE_ARF | UPDATE_LAST);
       }
       break;
     case INTER_LAYER_PREDICTION_I:
       if (si->layer == 0) {
         flags = map_vp8_flags(USE_LAST | UPDATE_LAST);
       } else if (is_keyframe) {
         flags = map_vp8_flags(USE_ARF | UPDATE_LAST);
       } else {
         flags = map_vp8_flags(USE_LAST | UPDATE_LAST);
       }
       break;
     case INTER_LAYER_PREDICTION_IP:
       if (si->layer == 0) {
         flags = map_vp8_flags(USE_LAST | UPDATE_LAST);
       } else if (is_keyframe) {
         flags = map_vp8_flags(USE_ARF | UPDATE_LAST);
       } else {
         flags = map_vp8_flags(USE_LAST | USE_ARF | UPDATE_LAST);
       }
       break;
     case USE_GOLDEN_FRAME:
       if (2 * si->layers - SVC_REFERENCE_FRAMES <= si->layer) {
         if (si->layer == 0) {
           flags = map_vp8_flags(USE_LAST | USE_GF | UPDATE_LAST);
         } else if (is_keyframe) {
           flags = map_vp8_flags(USE_ARF | UPDATE_LAST | UPDATE_GF);
         } else {
           flags = map_vp8_flags(USE_LAST | USE_ARF | USE_GF | UPDATE_LAST);
         }
       } else {
         if (si->layer == 0) {
           flags = map_vp8_flags(USE_LAST | UPDATE_LAST);
         } else if (is_keyframe) {
           flags = map_vp8_flags(USE_ARF | UPDATE_LAST);
         } else {
           flags = map_vp8_flags(USE_LAST | UPDATE_LAST);
         }
       }
       break;
     default:
       svc_log(svc_ctx, SVC_LOG_ERROR, "unexpected encoding mode: %d\n",
               svc_ctx->encoding_mode);
       break;
   }
   si->enc_frame_flags = flags;
 }
 vpx_codec_err_t vpx_svc_get_layer_resolution(const SvcContext *svc_ctx,
                                              int layer,
                                              unsigned int *width,
                                              unsigned int *height) {
   int w, h, index, num, den;
   const SvcInternal *const si = get_const_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL || width == NULL || height == NULL) {
     return VPX_CODEC_INVALID_PARAM;
   }
   if (layer < 0 || layer >= si->layers) return VPX_CODEC_INVALID_PARAM;
   index = layer + VPX_SS_MAX_LAYERS - si->layers;
   num = si->scaling_factor_num[index];
   den = si->scaling_factor_den[index];
   if (num == 0 || den == 0) return VPX_CODEC_INVALID_PARAM;
   w = si->width * num / den;
   h = si->height * num / den;
   // make height and width even to make chrome player happy
   w += w % 2;
   h += h % 2;
   *width = w;
   *height = h;
   return VPX_CODEC_OK;
 }
 static void set_svc_parameters(SvcContext *svc_ctx,
                                vpx_codec_ctx_t *codec_ctx) {
   int layer, layer_index;
   vpx_svc_parameters_t svc_params;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   memset(&svc_params, 0, sizeof(svc_params));
   svc_params.layer = si->layer;
   svc_params.flags = si->enc_frame_flags;
   layer = si->layer;
   if (svc_ctx->encoding_mode == ALT_INTER_LAYER_PREDICTION_IP &&
       si->frame_within_gop == 0) {
     // layers 1 & 3 don't exist in this mode, use the higher one
     if (layer == 0 || layer == 2) {
       layer += 1;
     }
   }
   if (VPX_CODEC_OK != vpx_svc_get_layer_resolution(svc_ctx, layer,
                                                    &svc_params.width,
                                                    &svc_params.height)) {
     svc_log(svc_ctx, SVC_LOG_ERROR, "vpx_svc_get_layer_resolution failed\n");
   }
   layer_index = layer + VPX_SS_MAX_LAYERS - si->layers;
   svc_params.min_quantizer = si->quantizer[layer_index];
   svc_params.max_quantizer = si->quantizer[layer_index];
   svc_params.distance_from_i_frame = si->frame_within_gop;
   // Use buffer i for layer i LST
   svc_params.lst_fb_idx = si->layer;
   // Use buffer i-1 for layer i Alt (Inter-layer prediction)
   if (si->layer != 0) {
     const int use_higher_layer =
         svc_ctx->encoding_mode == ALT_INTER_LAYER_PREDICTION_IP &&
         si->frame_within_gop == 0;
     svc_params.alt_fb_idx = use_higher_layer ? si->layer - 2 : si->layer - 1;
   }
   if (svc_ctx->encoding_mode == ALT_INTER_LAYER_PREDICTION_IP) {
     svc_params.gld_fb_idx = si->layer + 1;
   } else {
     if (si->layer < 2 * si->layers - SVC_REFERENCE_FRAMES)
       svc_params.gld_fb_idx = svc_params.lst_fb_idx;
     else
       svc_params.gld_fb_idx = 2 * si->layers - 1 - si->layer;
   }
   svc_log(svc_ctx, SVC_LOG_DEBUG, "SVC frame: %d, layer: %d, %dx%d, q: %d\n",
           si->encode_frame_count, si->layer, svc_params.width,
           svc_params.height, svc_params.min_quantizer);
   if (svc_params.flags == VPX_EFLAG_FORCE_KF) {
     svc_log(svc_ctx, SVC_LOG_DEBUG, "flags == VPX_EFLAG_FORCE_KF\n");
   } else {
     svc_log(
         svc_ctx, SVC_LOG_DEBUG, "Using:    LST/GLD/ALT [%2d|%2d|%2d]\n",
         svc_params.flags & VP8_EFLAG_NO_REF_LAST ? -1 : svc_params.lst_fb_idx,
         svc_params.flags & VP8_EFLAG_NO_REF_GF ? -1 : svc_params.gld_fb_idx,
         svc_params.flags & VP8_EFLAG_NO_REF_ARF ? -1 : svc_params.alt_fb_idx);
     svc_log(
         svc_ctx, SVC_LOG_DEBUG, "Updating: LST/GLD/ALT [%2d|%2d|%2d]\n",
         svc_params.flags & VP8_EFLAG_NO_UPD_LAST ? -1 : svc_params.lst_fb_idx,
         svc_params.flags & VP8_EFLAG_NO_UPD_GF ? -1 : svc_params.gld_fb_idx,
         svc_params.flags & VP8_EFLAG_NO_UPD_ARF ? -1 : svc_params.alt_fb_idx);
   }
   vpx_codec_control(codec_ctx, VP9E_SET_SVC_PARAMETERS, &svc_params);
 }
 /**
  * Encode a frame into multiple layers
  * Create a superframe containing the individual layers
  */
 vpx_codec_err_t vpx_svc_encode(SvcContext *svc_ctx, vpx_codec_ctx_t *codec_ctx,
                                struct vpx_image *rawimg, vpx_codec_pts_t pts,
                                int64_t duration, int deadline) {
   vpx_codec_err_t res;
   vpx_codec_iter_t iter;
   const vpx_codec_cx_pkt_t *cx_pkt;
   struct LayerData *cx_layer_list = NULL;
   struct LayerData *layer_data;
   struct Superframe superframe;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || codec_ctx == NULL || rawimg == NULL || si == NULL) {
     return VPX_CODEC_INVALID_PARAM;
   }
   memset(&superframe, 0, sizeof(superframe));
   svc_log_reset(svc_ctx);
   si->layers = vpx_svc_dummy_frame(svc_ctx) ? 1 : svc_ctx->spatial_layers;
   if (si->frame_within_gop >= si->kf_dist ||
       si->encode_frame_count == 0 ||
       (si->encode_frame_count == 1 && svc_ctx->first_frame_full_size == 1)) {
     si->frame_within_gop = 0;
   }
   si->is_keyframe = (si->frame_within_gop == 0);
   si->frame_size = 0;
   svc_log(svc_ctx, SVC_LOG_DEBUG,
           "vpx_svc_encode  layers: %d, frame_count: %d, frame_within_gop: %d\n",
           si->layers, si->encode_frame_count, si->frame_within_gop);
   // encode each layer
   for (si->layer = 0; si->layer < si->layers; ++si->layer) {
     if (svc_ctx->encoding_mode == ALT_INTER_LAYER_PREDICTION_IP &&
         si->is_keyframe && (si->layer == 1 || si->layer == 3)) {
       svc_log(svc_ctx, SVC_LOG_DEBUG, "Skip encoding layer %d\n", si->layer);
       continue;
     }
     calculate_enc_frame_flags(svc_ctx);
     if (vpx_svc_dummy_frame(svc_ctx)) {
       // do not set svc parameters, use normal encode
       svc_log(svc_ctx, SVC_LOG_DEBUG, "encoding full size first frame\n");
     } else {
       set_svc_parameters(svc_ctx, codec_ctx);
     }
     res = vpx_codec_encode(codec_ctx, rawimg, pts, (uint32_t)duration,
                            si->enc_frame_flags, deadline);
     if (res != VPX_CODEC_OK) {
       return res;
     }
     // save compressed data
     iter = NULL;
     while ((cx_pkt = vpx_codec_get_cx_data(codec_ctx, &iter))) {
       switch (cx_pkt->kind) {
         case VPX_CODEC_CX_FRAME_PKT: {
           const uint32_t frame_pkt_size = (uint32_t)(cx_pkt->data.frame.sz);
           if (!vpx_svc_dummy_frame(svc_ctx)) {
             si->bytes_in_layer[si->layer] += frame_pkt_size;
             svc_log(svc_ctx, SVC_LOG_DEBUG,
                     "SVC frame: %d, layer: %d, size: %u\n",
                     si->encode_frame_count, si->layer, frame_pkt_size);
           }
           layer_data =
               ld_create(cx_pkt->data.frame.buf, (size_t)frame_pkt_size);
           if (layer_data == NULL) {
             svc_log(svc_ctx, SVC_LOG_ERROR, "Error allocating LayerData\n");
             return 0;
           }
           ld_list_add(&cx_layer_list, layer_data);
           // save layer size in superframe index
           superframe.sizes[superframe.count++] = frame_pkt_size;
           superframe.magnitude |= frame_pkt_size;
           break;
         }
         case VPX_CODEC_PSNR_PKT: {
           if (!vpx_svc_dummy_frame(svc_ctx)) {
             svc_log(svc_ctx, SVC_LOG_DEBUG,
                     "SVC frame: %d, layer: %d, PSNR(Total/Y/U/V): "
                     "%2.3f  %2.3f  %2.3f  %2.3f \n",
                     si->encode_frame_count, si->layer,
                     cx_pkt->data.psnr.psnr[0], cx_pkt->data.psnr.psnr[1],
                     cx_pkt->data.psnr.psnr[2], cx_pkt->data.psnr.psnr[3]);
             si->psnr_in_layer[si->layer] += cx_pkt->data.psnr.psnr[0];
           }
           break;
         }
         default: {
           break;
         }
       }
     }
   }
   // add superframe index to layer data list
   if (!vpx_svc_dummy_frame(svc_ctx)) {
     sf_create_index(&superframe);
     layer_data = ld_create(superframe.buffer, superframe.index_size);
     ld_list_add(&cx_layer_list, layer_data);
   }
   // get accumulated size of layer data
   si->frame_size = ld_list_get_buffer_size(cx_layer_list);
   if (si->frame_size == 0) return VPX_CODEC_ERROR;
   // all layers encoded, create single buffer with concatenated layers
   if (si->frame_size > si->buffer_size) {
     free(si->buffer);
     si->buffer = malloc(si->frame_size);
     if (si->buffer == NULL) {
       ld_list_free(cx_layer_list);
       return VPX_CODEC_MEM_ERROR;
     }
     si->buffer_size = si->frame_size;
   }
   // copy layer data into packet
   ld_list_copy_to_buffer(cx_layer_list, si->buffer);
   ld_list_free(cx_layer_list);
   svc_log(svc_ctx, SVC_LOG_DEBUG, "SVC frame: %d, kf: %d, size: %d, pts: %d\n",
           si->encode_frame_count, si->is_keyframe, (int)si->frame_size,
           (int)pts);
   ++si->frame_within_gop;
   ++si->encode_frame_count;
   return VPX_CODEC_OK;
 }
 const char *vpx_svc_get_message(const SvcContext *svc_ctx) {
   const SvcInternal *const si = get_const_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return NULL;
   return si->message_buffer;
 }
 void *vpx_svc_get_buffer(const SvcContext *svc_ctx) {
   const SvcInternal *const si = get_const_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return NULL;
   return si->buffer;
 }
 size_t vpx_svc_get_frame_size(const SvcContext *svc_ctx) {
   const SvcInternal *const si = get_const_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return 0;
   return si->frame_size;
 }
 int vpx_svc_get_encode_frame_count(const SvcContext *svc_ctx) {
   const SvcInternal *const si = get_const_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return 0;
   return si->encode_frame_count;
 }
 int vpx_svc_is_keyframe(const SvcContext *svc_ctx) {
   const SvcInternal *const si = get_const_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return 0;
   return si->is_keyframe;
 }
 void vpx_svc_set_keyframe(SvcContext *svc_ctx) {
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return;
   si->frame_within_gop = 0;
 }
 // dump accumulated statistics and reset accumulated values
 const char *vpx_svc_dump_statistics(SvcContext *svc_ctx) {
   int number_of_frames, number_of_keyframes, encode_frame_count;
   int i;
   uint32_t bytes_total = 0;
   SvcInternal *const si = get_svc_internal(svc_ctx);
   if (svc_ctx == NULL || si == NULL) return NULL;
   svc_log_reset(svc_ctx);
   encode_frame_count = si->encode_frame_count;
   if (svc_ctx->first_frame_full_size) encode_frame_count--;
   if (si->encode_frame_count <= 0) return vpx_svc_get_message(svc_ctx);
   svc_log(svc_ctx, SVC_LOG_INFO, "\n");
   number_of_keyframes = encode_frame_count / si->kf_dist + 1;
   for (i = 0; i < si->layers; ++i) {
     number_of_frames = encode_frame_count;
     if (svc_ctx->encoding_mode == ALT_INTER_LAYER_PREDICTION_IP &&
         (i == 1 || i == 3)) {
       number_of_frames -= number_of_keyframes;
     }
     svc_log(svc_ctx, SVC_LOG_INFO, "Layer %d PSNR=[%2.3f], Bytes=[%u]\n", i,
             (double)si->psnr_in_layer[i] / number_of_frames,
             si->bytes_in_layer[i]);
     bytes_total += si->bytes_in_layer[i];
     si->psnr_in_layer[i] = 0;
     si->bytes_in_layer[i] = 0;
   }
   // only display statistics once
   si->encode_frame_count = 0;
   svc_log(svc_ctx, SVC_LOG_INFO, "Total Bytes=[%u]\n", bytes_total);
   return vpx_svc_get_message(svc_ctx);
 }
 void vpx_svc_release(SvcContext *svc_ctx) {
   SvcInternal *si;
   if (svc_ctx == NULL) return;
   // do not use get_svc_internal as it will unnecessarily allocate an
   // SvcInternal if it was not already allocated
   si = (SvcInternal *)svc_ctx->internal;
   if (si != NULL) {
     free(si->buffer);
     free(si);
     svc_ctx->internal = NULL;
   }
 }

The Tor Browser / annotate

media/libvpx/vpx/src/svc_encodeframe.c@ac0c01689b40 (annotated)

media/libvpx/vpx/src/svc_encodeframe.c