Function init_output_frame

doc/examples/transcode_aac.c:609–641

* Initialize one input frame for writing to the output file. * The frame will be exactly frame_size samples large. * @param[out] frame Frame to be initialized * @param output_codec_context Codec context of the output file * @param frame_size Size of the frame * @return Error code (0 if successful) */

 * @return Error code (0 if successful)
 */
static int init_output_frame(AVFrame **frame,
                             AVCodecContext *output_codec_context,
                             int frame_size)
{
    int error;

    /* Create a new frame to store the audio samples. */
    if (!(*frame = av_frame_alloc())) {
        fprintf(stderr, "Could not allocate output frame\n");
        return AVERROR_EXIT;
    }

    /* Set the frame's parameters, especially its size and format.
     * av_frame_get_buffer needs this to allocate memory for the
     * audio samples of the frame.
     * Default channel layouts based on the number of channels
     * are assumed for simplicity. */
    (*frame)->nb_samples     = frame_size;
    av_channel_layout_copy(&(*frame)->ch_layout, &output_codec_context->ch_layout);
    (*frame)->format         = output_codec_context->sample_fmt;
    (*frame)->sample_rate    = output_codec_context->sample_rate;

    /* Allocate the samples of the created frame. This call will make
     * sure that the audio frame can hold as many samples as specified. */
    if ((error = av_frame_get_buffer(*frame, 0)) < 0) {
        fprintf(stderr, "Could not allocate output frame samples (error '%s')\n",
                av_err2str(error));
        av_frame_free(frame);
        return error;
    }

    return 0;
}

/* Global timestamp for the audio frames. */
static int64_t pts = 0;