This source file includes following definitions.
- add_crc_to_array
- compare_crc_in_array
- compute_crc_of_packets
- read_seek_range
- seek_test
- main
#include "libavutil/adler32.h"
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libavutil/imgutils.h"
int64_t *pts_array;
uint32_t *crc_array;
int size_of_array;
int number_of_elements;
static int add_crc_to_array(uint32_t crc, int64_t pts)
{
if (size_of_array <= number_of_elements) {
if (size_of_array == 0)
size_of_array = 10;
size_of_array *= 2;
crc_array = av_realloc_f(crc_array, size_of_array, sizeof(uint32_t));
pts_array = av_realloc_f(pts_array, size_of_array, sizeof(int64_t));
if ((crc_array == NULL) || (pts_array == NULL)) {
av_log(NULL, AV_LOG_ERROR, "Can't allocate array to store crcs\n");
return AVERROR(ENOMEM);
}
}
crc_array[number_of_elements] = crc;
pts_array[number_of_elements] = pts;
number_of_elements++;
return 0;
}
static int compare_crc_in_array(uint32_t crc, int64_t pts)
{
int i;
for (i = 0; i < number_of_elements; i++) {
if (pts_array[i] == pts) {
if (crc_array[i] == crc) {
printf("Comparing 0x%08"PRIx32" %"PRId64" %d is OK\n", crc, pts, i);
return 0;
}
else {
av_log(NULL, AV_LOG_ERROR, "Incorrect crc of a frame after seeking\n");
return -1;
}
}
}
av_log(NULL, AV_LOG_ERROR, "Incorrect pts of a frame after seeking\n");
return -1;
}
static int compute_crc_of_packets(AVFormatContext *fmt_ctx, int video_stream,
AVCodecContext *ctx, AVFrame *fr, uint64_t ts_start, uint64_t ts_end, int no_seeking)
{
int number_of_written_bytes;
int got_frame = 0;
int result;
int end_of_stream = 0;
int byte_buffer_size;
uint8_t *byte_buffer;
uint32_t crc;
AVPacket pkt;
byte_buffer_size = av_image_get_buffer_size(ctx->pix_fmt, ctx->width, ctx->height, 16);
byte_buffer = av_malloc(byte_buffer_size);
if (!byte_buffer) {
av_log(NULL, AV_LOG_ERROR, "Can't allocate buffer\n");
return AVERROR(ENOMEM);
}
if (!no_seeking) {
result = av_seek_frame(fmt_ctx, video_stream, ts_start, AVSEEK_FLAG_ANY);
printf("Seeking to %"PRId64", computing crc for frames with pts < %"PRId64"\n", ts_start, ts_end);
if (result < 0) {
av_log(NULL, AV_LOG_ERROR, "Error in seeking\n");
return result;
}
avcodec_flush_buffers(ctx);
}
av_init_packet(&pkt);
do {
if (!end_of_stream)
if (av_read_frame(fmt_ctx, &pkt) < 0)
end_of_stream = 1;
if (end_of_stream) {
pkt.data = NULL;
pkt.size = 0;
}
if (pkt.stream_index == video_stream || end_of_stream) {
got_frame = 0;
if ((pkt.pts == AV_NOPTS_VALUE) && (!end_of_stream)) {
av_log(NULL, AV_LOG_ERROR, "Error: frames doesn't have pts values\n");
return -1;
}
result = avcodec_decode_video2(ctx, fr, &got_frame, &pkt);
if (result < 0) {
av_log(NULL, AV_LOG_ERROR, "Error decoding frame\n");
return result;
}
if (got_frame) {
number_of_written_bytes = av_image_copy_to_buffer(byte_buffer, byte_buffer_size,
(const uint8_t* const *)fr->data, (const int*) fr->linesize,
ctx->pix_fmt, ctx->width, ctx->height, 1);
if (number_of_written_bytes < 0) {
av_log(NULL, AV_LOG_ERROR, "Can't copy image to buffer\n");
return number_of_written_bytes;
}
if ((!no_seeking) && (fr->pts > ts_end))
break;
crc = av_adler32_update(0, (const uint8_t*)byte_buffer, number_of_written_bytes);
printf("%10"PRId64", 0x%08"PRIx32"\n", fr->pts, crc);
if (no_seeking) {
if (add_crc_to_array(crc, fr->pts) < 0)
return -1;
}
else {
if (compare_crc_in_array(crc, fr->pts) < 0)
return -1;
}
}
}
av_packet_unref(&pkt);
av_init_packet(&pkt);
} while ((!end_of_stream || got_frame) && (no_seeking || (fr->pts + fr->pkt_duration <= ts_end)));
av_packet_unref(&pkt);
av_freep(&byte_buffer);
return 0;
}
static long int read_seek_range(const char *string_with_number)
{
long int number;
char *end_of_string = NULL;
number = strtol(string_with_number, &end_of_string, 10);
if ((strlen(string_with_number) != end_of_string - string_with_number) || (number < 0)) {
av_log(NULL, AV_LOG_ERROR, "Incorrect input ranges of seeking\n");
return -1;
}
else if ((number == LONG_MAX) || (number == LONG_MIN)) {
if (errno == ERANGE) {
av_log(NULL, AV_LOG_ERROR, "Incorrect input ranges of seeking\n");
return -1;
}
}
return number;
}
static int seek_test(const char *input_filename, const char *start, const char *end)
{
AVCodec *codec = NULL;
AVCodecContext *ctx= NULL;
AVCodecParameters *origin_par = NULL;
AVFrame *fr = NULL;
AVFormatContext *fmt_ctx = NULL;
int video_stream;
int result;
int i, j;
long int start_ts, end_ts;
size_of_array = 0;
number_of_elements = 0;
crc_array = NULL;
pts_array = NULL;
result = avformat_open_input(&fmt_ctx, input_filename, NULL, NULL);
if (result < 0) {
av_log(NULL, AV_LOG_ERROR, "Can't open file\n");
return result;
}
result = avformat_find_stream_info(fmt_ctx, NULL);
if (result < 0) {
av_log(NULL, AV_LOG_ERROR, "Can't get stream info\n");
goto end;
}
start_ts = read_seek_range(start);
end_ts = read_seek_range(end);
if ((start_ts < 0) || (end_ts < 0)) {
result = -1;
goto end;
}
video_stream = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, NULL, 0);
if (video_stream < 0) {
av_log(NULL, AV_LOG_ERROR, "Can't find video stream in input file\n");
result = video_stream;
goto end;
}
origin_par = fmt_ctx->streams[video_stream]->codecpar;
codec = avcodec_find_decoder(origin_par->codec_id);
if (!codec) {
av_log(NULL, AV_LOG_ERROR, "Can't find decoder\n");
result = AVERROR_DECODER_NOT_FOUND;
goto end;
}
ctx = avcodec_alloc_context3(codec);
if (!ctx) {
av_log(NULL, AV_LOG_ERROR, "Can't allocate decoder context\n");
result = AVERROR(ENOMEM);
goto end;
}
result = avcodec_parameters_to_context(ctx, origin_par);
if (result) {
av_log(NULL, AV_LOG_ERROR, "Can't copy decoder context\n");
goto end;
}
result = avcodec_open2(ctx, codec, NULL);
if (result < 0) {
av_log(ctx, AV_LOG_ERROR, "Can't open decoder\n");
goto end;
}
fr = av_frame_alloc();
if (!fr) {
av_log(NULL, AV_LOG_ERROR, "Can't allocate frame\n");
result = AVERROR(ENOMEM);
goto end;
}
result = compute_crc_of_packets(fmt_ctx, video_stream, ctx, fr, 0, 0, 1);
if (result != 0)
goto end;
for (i = start_ts; i < end_ts; i += 100) {
for (j = i + 100; j < end_ts; j += 100) {
result = compute_crc_of_packets(fmt_ctx, video_stream, ctx, fr, i, j, 0);
if (result != 0)
break;
}
}
end:
av_freep(&crc_array);
av_freep(&pts_array);
av_frame_free(&fr);
avcodec_close(ctx);
avformat_close_input(&fmt_ctx);
avcodec_free_context(&ctx);
return result;
}
int main(int argc, char **argv)
{
if (argc < 4) {
av_log(NULL, AV_LOG_ERROR, "Incorrect input\n");
return 1;
}
if (seek_test(argv[1], argv[2], argv[3]) != 0)
return 1;
return 0;
}