utils.c

        if (avctx->codec->pix_fmts) {
            for (i = 0; avctx->codec->pix_fmts[i] != AV_PIX_FMT_NONE; i++)
                if (avctx->pix_fmt == avctx->codec->pix_fmts[i])
                    break;
            if (avctx->codec->pix_fmts[i] == AV_PIX_FMT_NONE) {
                av_log(avctx, AV_LOG_ERROR, "Specified pix_fmt is not supported\n");
                ret = AVERROR(EINVAL);
                goto free_and_end;
            }
            if (avctx->codec->pix_fmts[i] == AV_PIX_FMT_YUVJ420P ||
                avctx->codec->pix_fmts[i] == AV_PIX_FMT_YUVJ422P ||
                avctx->codec->pix_fmts[i] == AV_PIX_FMT_YUVJ440P ||
                avctx->codec->pix_fmts[i] == AV_PIX_FMT_YUVJ444P)
                avctx->color_range = AVCOL_RANGE_JPEG;
        }
        if (avctx->codec->supported_samplerates) {
            for (i = 0; avctx->codec->supported_samplerates[i] != 0; i++)
                if (avctx->sample_rate == avctx->codec->supported_samplerates[i])
                    break;
            if (avctx->codec->supported_samplerates[i] == 0) {
                av_log(avctx, AV_LOG_ERROR, "Specified sample_rate is not supported\n");
                ret = AVERROR(EINVAL);
                goto free_and_end;
            }
        }
        if (avctx->codec->channel_layouts) {
            if (!avctx->channel_layout) {
                av_log(avctx, AV_LOG_WARNING, "channel_layout not specified\n");
            } else {
                for (i = 0; avctx->codec->channel_layouts[i] != 0; i++)
                    if (avctx->channel_layout == avctx->codec->channel_layouts[i])
                        break;
                if (avctx->codec->channel_layouts[i] == 0) {
                    av_log(avctx, AV_LOG_ERROR, "Specified channel_layout is not supported\n");
                    ret = AVERROR(EINVAL);
                    goto free_and_end;
                }
            }
        }
        if (avctx->channel_layout && avctx->channels) {
            if (av_get_channel_layout_nb_channels(avctx->channel_layout) != avctx->channels) {
                av_log(avctx, AV_LOG_ERROR, "channel layout does not match number of channels\n");
                ret = AVERROR(EINVAL);
                goto free_and_end;
            }
        } else if (avctx->channel_layout) {
            avctx->channels = av_get_channel_layout_nb_channels(avctx->channel_layout);
        }

        if (!avctx->rc_initial_buffer_occupancy)
            avctx->rc_initial_buffer_occupancy = avctx->rc_buffer_size * 3 / 4;
    }

    if (avctx->codec->init && !(avctx->active_thread_type & FF_THREAD_FRAME)) {
        ret = avctx->codec->init(avctx);
        if (ret < 0) {
            goto free_and_end;
        }
    }

#if FF_API_AUDIOENC_DELAY
    if (av_codec_is_encoder(avctx->codec))
        avctx->delay = avctx->initial_padding;
#endif

    if (av_codec_is_decoder(avctx->codec)) {
        /* validate channel layout from the decoder */
        if (avctx->channel_layout) {
            int channels = av_get_channel_layout_nb_channels(avctx->channel_layout);
            if (!avctx->channels)
                avctx->channels = channels;
            else if (channels != avctx->channels) {
                av_log(avctx, AV_LOG_WARNING,
                       "channel layout does not match number of channels\n");
                avctx->channel_layout = 0;
            }
        }
        if (avctx->channels && avctx->channels < 0 ||
            avctx->channels > FF_SANE_NB_CHANNELS) {
            ret = AVERROR(EINVAL);
            goto free_and_end;
        }

#if FF_API_AVCTX_TIMEBASE
        if (avctx->framerate.num > 0 && avctx->framerate.den > 0)
            avctx->time_base = av_inv_q(avctx->framerate);
#endif
    }
end:
    if (!(codec->caps_internal & FF_CODEC_CAP_INIT_THREADSAFE) && codec->init) {
        entangled_thread_counter--;

        /* Release any user-supplied mutex. */
        if (lockmgr_cb) {
            (*lockmgr_cb)(&codec_mutex, AV_LOCK_RELEASE);
        }
    }

    if (options) {
        av_dict_free(options);
        *options = tmp;
    }

    return ret;
free_and_end:
    if (avctx->codec &&
        (avctx->codec->caps_internal & FF_CODEC_CAP_INIT_CLEANUP))
        avctx->codec->close(avctx);

    if (avctx->priv_data && avctx->codec && avctx->codec->priv_class)
        av_opt_free(avctx->priv_data);
    av_opt_free(avctx);

#if FF_API_CODED_FRAME
FF_DISABLE_DEPRECATION_WARNINGS
    av_frame_free(&avctx->coded_frame);
FF_ENABLE_DEPRECATION_WARNINGS
#endif

    av_dict_free(&tmp);
    av_freep(&avctx->priv_data);
    if (avctx->internal) {
        av_frame_free(&avctx->internal->to_free);
        av_freep(&avctx->internal->pool);
    }
    av_freep(&avctx->internal);
    avctx->codec = NULL;
    goto end;
}

int ff_alloc_packet(AVPacket *avpkt, int size)
{
    if (size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
        return AVERROR(EINVAL);

    if (avpkt->data) {
        AVBufferRef *buf = avpkt->buf;

        if (avpkt->size < size)
            return AVERROR(EINVAL);

        av_init_packet(avpkt);
        avpkt->buf      = buf;
        avpkt->size     = size;
        return 0;
    } else {
        return av_new_packet(avpkt, size);
    }
}

/**
 * Pad last frame with silence.
 */
static int pad_last_frame(AVCodecContext *s, AVFrame **dst, const AVFrame *src)
{
    AVFrame *frame = NULL;
    int ret;

    if (!(frame = av_frame_alloc()))
        return AVERROR(ENOMEM);

    frame->format         = src->format;
    frame->channel_layout = src->channel_layout;
    frame->nb_samples     = s->frame_size;
    ret = av_frame_get_buffer(frame, 32);
    if (ret < 0)
        goto fail;

    ret = av_frame_copy_props(frame, src);
    if (ret < 0)
        goto fail;

    if ((ret = av_samples_copy(frame->extended_data, src->extended_data, 0, 0,
                               src->nb_samples, s->channels, s->sample_fmt)) < 0)
        goto fail;
    if ((ret = av_samples_set_silence(frame->extended_data, src->nb_samples,
                                      frame->nb_samples - src->nb_samples,
                                      s->channels, s->sample_fmt)) < 0)
        goto fail;

    *dst = frame;

    return 0;

fail:
    av_frame_free(&frame);
    return ret;
}

int attribute_align_arg avcodec_encode_audio2(AVCodecContext *avctx,
                                              AVPacket *avpkt,
                                              const AVFrame *frame,
                                              int *got_packet_ptr)
{
    AVFrame tmp;
    AVFrame *padded_frame = NULL;
    int ret;
    int user_packet = !!avpkt->data;

    *got_packet_ptr = 0;

    if (!(avctx->codec->capabilities & AV_CODEC_CAP_DELAY) && !frame) {
        av_packet_unref(avpkt);
        av_init_packet(avpkt);
        return 0;
    }

    /* ensure that extended_data is properly set */
    if (frame && !frame->extended_data) {
        if (av_sample_fmt_is_planar(avctx->sample_fmt) &&
            avctx->channels > AV_NUM_DATA_POINTERS) {
            av_log(avctx, AV_LOG_ERROR, "Encoding to a planar sample format, "
                                        "with more than %d channels, but extended_data is not set.\n",
                   AV_NUM_DATA_POINTERS);
            return AVERROR(EINVAL);
        }
        av_log(avctx, AV_LOG_WARNING, "extended_data is not set.\n");

        tmp = *frame;
        tmp.extended_data = tmp.data;
        frame = &tmp;
    }

    /* extract audio service type metadata */
    if (frame) {
        AVFrameSideData *sd = av_frame_get_side_data(frame, AV_FRAME_DATA_AUDIO_SERVICE_TYPE);
        if (sd && sd->size >= sizeof(enum AVAudioServiceType))
            avctx->audio_service_type = *(enum AVAudioServiceType*)sd->data;
    }

    /* check for valid frame size */
    if (frame) {
        if (avctx->codec->capabilities & AV_CODEC_CAP_SMALL_LAST_FRAME) {
            if (frame->nb_samples > avctx->frame_size)
                return AVERROR(EINVAL);
        } else if (!(avctx->codec->capabilities & AV_CODEC_CAP_VARIABLE_FRAME_SIZE)) {
            if (frame->nb_samples < avctx->frame_size &&
                !avctx->internal->last_audio_frame) {
                ret = pad_last_frame(avctx, &padded_frame, frame);
                if (ret < 0)
                    return ret;

                frame = padded_frame;
                avctx->internal->last_audio_frame = 1;
            }

            if (frame->nb_samples != avctx->frame_size) {
                ret = AVERROR(EINVAL);
                goto end;
            }
        }
    }

    ret = avctx->codec->encode2(avctx, avpkt, frame, got_packet_ptr);
    if (!ret) {
        if (*got_packet_ptr) {
            if (!(avctx->codec->capabilities & AV_CODEC_CAP_DELAY)) {
                if (avpkt->pts == AV_NOPTS_VALUE)
                    avpkt->pts = frame->pts;
                if (!avpkt->duration)
                    avpkt->duration = ff_samples_to_time_base(avctx,
                                                              frame->nb_samples);
            }
            avpkt->dts = avpkt->pts;
        } else {
            avpkt->size = 0;
        }

        if (!user_packet && avpkt->size) {
            ret = av_buffer_realloc(&avpkt->buf, avpkt->size);
            if (ret >= 0)
                avpkt->data = avpkt->buf->data;
        }

        avctx->frame_number++;
    }

    if (ret < 0 || !*got_packet_ptr) {
        av_packet_unref(avpkt);
        av_init_packet(avpkt);
        goto end;
    }

    /* NOTE: if we add any audio encoders which output non-keyframe packets,
     *       this needs to be moved to the encoders, but for now we can do it
     *       here to simplify things */
    avpkt->flags |= AV_PKT_FLAG_KEY;

end:
    av_frame_free(&padded_frame);

#if FF_API_AUDIOENC_DELAY
    avctx->delay = avctx->initial_padding;
#endif

    return ret;
}

int attribute_align_arg avcodec_encode_video2(AVCodecContext *avctx,
                                              AVPacket *avpkt,
                                              const AVFrame *frame,
                                              int *got_packet_ptr)
{
    int ret;
    int user_packet = !!avpkt->data;

    *got_packet_ptr = 0;

    if (!(avctx->codec->capabilities & AV_CODEC_CAP_DELAY) && !frame) {
        av_packet_unref(avpkt);
        av_init_packet(avpkt);
        avpkt->size = 0;
        return 0;
    }

    if (av_image_check_size(avctx->width, avctx->height, 0, avctx))
        return AVERROR(EINVAL);

    av_assert0(avctx->codec->encode2);

    ret = avctx->codec->encode2(avctx, avpkt, frame, got_packet_ptr);
    if (!ret) {
        if (!*got_packet_ptr)
            avpkt->size = 0;
        else if (!(avctx->codec->capabilities & AV_CODEC_CAP_DELAY))
            avpkt->pts = avpkt->dts = frame->pts;

        if (!user_packet && avpkt->size) {
            ret = av_buffer_realloc(&avpkt->buf, avpkt->size);
            if (ret >= 0)
                avpkt->data = avpkt->buf->data;
        }

        avctx->frame_number++;
    }

    if (ret < 0 || !*got_packet_ptr)
        av_packet_unref(avpkt);

    emms_c();
    return ret;
}

int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
                            const AVSubtitle *sub)
{
    int ret;
    if (sub->start_display_time) {
        av_log(avctx, AV_LOG_ERROR, "start_display_time must be 0.\n");
        return -1;
    }
    if (sub->num_rects == 0 || !sub->rects)
        return -1;
    ret = avctx->codec->encode_sub(avctx, buf, buf_size, sub);
    avctx->frame_number++;
    return ret;
}

static int apply_param_change(AVCodecContext *avctx, AVPacket *avpkt)
{
    int size = 0, ret;
    const uint8_t *data;
    uint32_t flags;

    data = av_packet_get_side_data(avpkt, AV_PKT_DATA_PARAM_CHANGE, &size);
    if (!data)
        return 0;

    if (!(avctx->codec->capabilities & AV_CODEC_CAP_PARAM_CHANGE)) {
        av_log(avctx, AV_LOG_ERROR, "This decoder does not support parameter "
               "changes, but PARAM_CHANGE side data was sent to it.\n");
        return AVERROR(EINVAL);
    }

    if (size < 4)
        goto fail;

    flags = bytestream_get_le32(&data);
    size -= 4;

    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT) {
        if (size < 4)
            goto fail;
        avctx->channels = bytestream_get_le32(&data);
        size -= 4;
    }
    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT) {
        if (size < 8)
            goto fail;
        avctx->channel_layout = bytestream_get_le64(&data);
        size -= 8;
    }
    if (flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE) {
        if (size < 4)
            goto fail;
        avctx->sample_rate = bytestream_get_le32(&data);
        size -= 4;
    }
    if (flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS) {
        if (size < 8)
            goto fail;
        avctx->width  = bytestream_get_le32(&data);
        avctx->height = bytestream_get_le32(&data);
        size -= 8;
        ret = ff_set_dimensions(avctx, avctx->width, avctx->height);
        if (ret < 0)
            return ret;
    }

    return 0;
fail:
    av_log(avctx, AV_LOG_ERROR, "PARAM_CHANGE side data too small.\n");
    return AVERROR_INVALIDDATA;
}

static int unrefcount_frame(AVCodecInternal *avci, AVFrame *frame)
{
    int ret;

    /* move the original frame to our backup */
    av_frame_unref(avci->to_free);
    av_frame_move_ref(avci->to_free, frame);

    /* now copy everything except the AVBufferRefs back
     * note that we make a COPY of the side data, so calling av_frame_free() on
     * the caller's frame will work properly */
    ret = av_frame_copy_props(frame, avci->to_free);
    if (ret < 0)
        return ret;

    memcpy(frame->data,     avci->to_free->data,     sizeof(frame->data));
    memcpy(frame->linesize, avci->to_free->linesize, sizeof(frame->linesize));
    if (avci->to_free->extended_data != avci->to_free->data) {
        int planes = av_get_channel_layout_nb_channels(avci->to_free->channel_layout);
        int size   = planes * sizeof(*frame->extended_data);

        if (!size) {
            av_frame_unref(frame);
            return AVERROR_BUG;
        }

        frame->extended_data = av_malloc(size);
        if (!frame->extended_data) {
            av_frame_unref(frame);
            return AVERROR(ENOMEM);
        }
        memcpy(frame->extended_data, avci->to_free->extended_data,
               size);
    } else
        frame->extended_data = frame->data;

    frame->format         = avci->to_free->format;
    frame->width          = avci->to_free->width;
    frame->height         = avci->to_free->height;
    frame->channel_layout = avci->to_free->channel_layout;
    frame->nb_samples     = avci->to_free->nb_samples;

    return 0;
}

int attribute_align_arg avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
                                              int *got_picture_ptr,
                                              AVPacket *avpkt)
{
    AVCodecInternal *avci = avctx->internal;
    int ret;

    *got_picture_ptr = 0;
    if ((avctx->coded_width || avctx->coded_height) && av_image_check_size(avctx->coded_width, avctx->coded_height, 0, avctx))
        return -1;

    avctx->internal->pkt = avpkt;
    ret = apply_param_change(avctx, avpkt);
    if (ret < 0) {
        av_log(avctx, AV_LOG_ERROR, "Error applying parameter changes.\n");
        if (avctx->err_recognition & AV_EF_EXPLODE)
            return ret;
    }

    av_frame_unref(picture);

    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size ||
        (avctx->active_thread_type & FF_THREAD_FRAME)) {
        if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME)
            ret = ff_thread_decode_frame(avctx, picture, got_picture_ptr,
                                         avpkt);
        else {
            ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
                                       avpkt);
            if (!(avctx->codec->caps_internal & FF_CODEC_CAP_SETS_PKT_DTS))
                picture->pkt_dts = avpkt->dts;
            /* get_buffer is supposed to set frame parameters */
            if (!(avctx->codec->capabilities & AV_CODEC_CAP_DR1)) {
                picture->sample_aspect_ratio = avctx->sample_aspect_ratio;
                picture->width               = avctx->width;
                picture->height              = avctx->height;
                picture->format              = avctx->pix_fmt;
            }
        }

        emms_c(); //needed to avoid an emms_c() call before every return;

        if (*got_picture_ptr) {
            if (!avctx->refcounted_frames) {
                int err = unrefcount_frame(avci, picture);
                if (err < 0)
                    return err;
            }

            avctx->frame_number++;
        } else
            av_frame_unref(picture);
    } else
        ret = 0;

#if FF_API_AVCTX_TIMEBASE
    if (avctx->framerate.num > 0 && avctx->framerate.den > 0)
        avctx->time_base = av_inv_q(avctx->framerate);
#endif

    return ret;
}

int attribute_align_arg avcodec_decode_audio4(AVCodecContext *avctx,
                                              AVFrame *frame,
                                              int *got_frame_ptr,
                                              AVPacket *avpkt)
{
    AVCodecInternal *avci = avctx->internal;
    int ret = 0;

    *got_frame_ptr = 0;

    avctx->internal->pkt = avpkt;

    if (!avpkt->data && avpkt->size) {
        av_log(avctx, AV_LOG_ERROR, "invalid packet: NULL data, size != 0\n");
        return AVERROR(EINVAL);
    }

    ret = apply_param_change(avctx, avpkt);
    if (ret < 0) {
        av_log(avctx, AV_LOG_ERROR, "Error applying parameter changes.\n");
        if (avctx->err_recognition & AV_EF_EXPLODE)
            return ret;
    }

    av_frame_unref(frame);

    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size) {
        ret = avctx->codec->decode(avctx, frame, got_frame_ptr, avpkt);
        if (ret >= 0 && *got_frame_ptr) {
            avctx->frame_number++;
            frame->pkt_dts = avpkt->dts;
            if (frame->format == AV_SAMPLE_FMT_NONE)
                frame->format = avctx->sample_fmt;

            if (!avctx->refcounted_frames) {
                int err = unrefcount_frame(avci, frame);
                if (err < 0)
                    return err;
            }
        } else
            av_frame_unref(frame);
    }


    return ret;
}

int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
                             int *got_sub_ptr,
                             AVPacket *avpkt)
{
    int ret;

    avctx->internal->pkt = avpkt;
    *got_sub_ptr = 0;
    ret = avctx->codec->decode(avctx, sub, got_sub_ptr, avpkt);
    if (*got_sub_ptr)
        avctx->frame_number++;
    return ret;
}

void avsubtitle_free(AVSubtitle *sub)
{
    int i;

    for (i = 0; i < sub->num_rects; i++) {
        av_freep(&sub->rects[i]->data[0]);
        av_freep(&sub->rects[i]->data[1]);
        av_freep(&sub->rects[i]->data[2]);
        av_freep(&sub->rects[i]->data[3]);
        av_freep(&sub->rects[i]->text);
        av_freep(&sub->rects[i]->ass);
        av_freep(&sub->rects[i]);
    }

    av_freep(&sub->rects);

    memset(sub, 0, sizeof(AVSubtitle));
}

av_cold int avcodec_close(AVCodecContext *avctx)
{
    int i;

    if (avcodec_is_open(avctx)) {
        FramePool *pool = avctx->internal->pool;

        if (HAVE_THREADS && avctx->internal->thread_ctx)
            ff_thread_free(avctx);
        if (avctx->codec && avctx->codec->close)
            avctx->codec->close(avctx);
        av_frame_free(&avctx->internal->to_free);
        for (i = 0; i < FF_ARRAY_ELEMS(pool->pools); i++)
            av_buffer_pool_uninit(&pool->pools[i]);
        av_freep(&avctx->internal->pool);

        if (avctx->hwaccel && avctx->hwaccel->uninit)
            avctx->hwaccel->uninit(avctx);
        av_freep(&avctx->internal->hwaccel_priv_data);

        av_freep(&avctx->internal);
    }

    for (i = 0; i < avctx->nb_coded_side_data; i++)
        av_freep(&avctx->coded_side_data[i].data);
    av_freep(&avctx->coded_side_data);
    avctx->nb_coded_side_data = 0;

    if (avctx->priv_data && avctx->codec && avctx->codec->priv_class)
        av_opt_free(avctx->priv_data);
    av_opt_free(avctx);
    av_freep(&avctx->priv_data);
    if (av_codec_is_encoder(avctx->codec)) {
        av_freep(&avctx->extradata);
#if FF_API_CODED_FRAME
FF_DISABLE_DEPRECATION_WARNINGS
        av_frame_free(&avctx->coded_frame);
FF_ENABLE_DEPRECATION_WARNINGS
#endif
    }
    avctx->codec = NULL;
    avctx->active_thread_type = 0;

    return 0;
}

static AVCodec *find_encdec(enum AVCodecID id, int encoder)
{
    AVCodec *p, *experimental = NULL;
    p = first_avcodec;
    while (p) {
        if ((encoder ? av_codec_is_encoder(p) : av_codec_is_decoder(p)) &&
            p->id == id) {
            if (p->capabilities & AV_CODEC_CAP_EXPERIMENTAL && !experimental) {
                experimental = p;
            } else
                return p;
        }
        p = p->next;
    }
    return experimental;
}

AVCodec *avcodec_find_encoder(enum AVCodecID id)
{
    return find_encdec(id, 1);
}

AVCodec *avcodec_find_encoder_by_name(const char *name)
{
    AVCodec *p;
    if (!name)
        return NULL;
    p = first_avcodec;
    while (p) {
        if (av_codec_is_encoder(p) && strcmp(name, p->name) == 0)
            return p;
        p = p->next;
    }
    return NULL;
}

AVCodec *avcodec_find_decoder(enum AVCodecID id)
{
    return find_encdec(id, 0);
}

AVCodec *avcodec_find_decoder_by_name(const char *name)
{
    AVCodec *p;
    if (!name)
        return NULL;
    p = first_avcodec;
    while (p) {
        if (av_codec_is_decoder(p) && strcmp(name, p->name) == 0)
            return p;
        p = p->next;
    }
    return NULL;
}

static int get_bit_rate(AVCodecContext *ctx)
{
    int bit_rate;
    int bits_per_sample;

    switch (ctx->codec_type) {
    case AVMEDIA_TYPE_VIDEO:
    case AVMEDIA_TYPE_DATA:
    case AVMEDIA_TYPE_SUBTITLE:
    case AVMEDIA_TYPE_ATTACHMENT:
        bit_rate = ctx->bit_rate;
        break;
    case AVMEDIA_TYPE_AUDIO:
        bits_per_sample = av_get_bits_per_sample(ctx->codec_id);
        bit_rate = bits_per_sample ? ctx->sample_rate * ctx->channels * bits_per_sample : ctx->bit_rate;
        break;
    default:
        bit_rate = 0;
        break;
    }
    return bit_rate;
}

size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag)
{
    int i, len, ret = 0;

#define TAG_PRINT(x)                                              \
    (((x) >= '0' && (x) <= '9') ||                                \
     ((x) >= 'a' && (x) <= 'z') || ((x) >= 'A' && (x) <= 'Z') ||  \
     ((x) == '.' || (x) == ' '))

    for (i = 0; i < 4; i++) {
        len = snprintf(buf, buf_size,
                       TAG_PRINT(codec_tag & 0xFF) ? "%c" : "[%d]", codec_tag & 0xFF);
        buf        += len;
        buf_size    = buf_size > len ? buf_size - len : 0;
        ret        += len;
        codec_tag >>= 8;
    }
    return ret;
}

void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
{
    const char *codec_name;
    const char *profile = NULL;
    const AVCodec *p;
    char buf1[32];
    int bitrate;
    int new_line = 0;
    AVRational display_aspect_ratio;

    if (enc->codec)
        p = enc->codec;
    else if (encode)
        p = avcodec_find_encoder(enc->codec_id);
    else
        p = avcodec_find_decoder(enc->codec_id);

    if (p) {
        codec_name = p->name;
        profile = av_get_profile_name(p, enc->profile);
    } else if (enc->codec_id == AV_CODEC_ID_MPEG2TS) {
        /* fake mpeg2 transport stream codec (currently not
         * registered) */
        codec_name = "mpeg2ts";
    } else {
        /* output avi tags */
        char tag_buf[32];
        av_get_codec_tag_string(tag_buf, sizeof(tag_buf), enc->codec_tag);
        snprintf(buf1, sizeof(buf1), "%s / 0x%04X", tag_buf, enc->codec_tag);
        codec_name = buf1;
    }

    switch (enc->codec_type) {
    case AVMEDIA_TYPE_VIDEO:
        snprintf(buf, buf_size,
                 "Video: %s%s",
                 codec_name, enc->mb_decision ? " (hq)" : "");
        if (profile)
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     " (%s)", profile);
        if (enc->codec_tag) {
            char tag_buf[32];
            av_get_codec_tag_string(tag_buf, sizeof(tag_buf), enc->codec_tag);
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     " [%s / 0x%04X]", tag_buf, enc->codec_tag);
        }

        av_strlcat(buf, "\n      ", buf_size);
        snprintf(buf + strlen(buf), buf_size - strlen(buf),
                 "%s", enc->pix_fmt == AV_PIX_FMT_NONE ? "none" :
                     av_get_pix_fmt_name(enc->pix_fmt));

        if (enc->color_range != AVCOL_RANGE_UNSPECIFIED)
            snprintf(buf + strlen(buf), buf_size - strlen(buf), ", %s",
                     av_color_range_name(enc->color_range));
        if (enc->colorspace != AVCOL_SPC_UNSPECIFIED ||
            enc->color_primaries != AVCOL_PRI_UNSPECIFIED ||
            enc->color_trc != AVCOL_TRC_UNSPECIFIED) {
            new_line = 1;
            snprintf(buf + strlen(buf), buf_size - strlen(buf), ", %s/%s/%s",
                     av_color_space_name(enc->colorspace),
                     av_color_primaries_name(enc->color_primaries),
                     av_color_transfer_name(enc->color_trc));
        }
        if (av_log_get_level() >= AV_LOG_DEBUG &&
            enc->chroma_sample_location != AVCHROMA_LOC_UNSPECIFIED)
            snprintf(buf + strlen(buf), buf_size - strlen(buf), ", %s",
                     av_chroma_location_name(enc->chroma_sample_location));

        if (enc->width) {
            av_strlcat(buf, new_line ? "\n      " : ", ", buf_size);

            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     "%dx%d",
                     enc->width, enc->height);

            if (av_log_get_level() >= AV_LOG_VERBOSE &&
                (enc->width != enc->coded_width ||
                 enc->height != enc->coded_height))
                snprintf(buf + strlen(buf), buf_size - strlen(buf),
                         " (%dx%d)", enc->coded_width, enc->coded_height);

            if (enc->sample_aspect_ratio.num) {
                av_reduce(&display_aspect_ratio.num, &display_aspect_ratio.den,
                          enc->width * enc->sample_aspect_ratio.num,
                          enc->height * enc->sample_aspect_ratio.den,
                          1024 * 1024);
                snprintf(buf + strlen(buf), buf_size - strlen(buf),
                         " [PAR %d:%d DAR %d:%d]",
                         enc->sample_aspect_ratio.num, enc->sample_aspect_ratio.den,
                         display_aspect_ratio.num, display_aspect_ratio.den);
            }
            if (av_log_get_level() >= AV_LOG_DEBUG) {
                int g = av_gcd(enc->time_base.num, enc->time_base.den);
                snprintf(buf + strlen(buf), buf_size - strlen(buf),
                         ", %d/%d",
                         enc->time_base.num / g, enc->time_base.den / g);
            }
        }
        if (encode) {
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     ", q=%d-%d", enc->qmin, enc->qmax);
        }
        break;
    case AVMEDIA_TYPE_AUDIO:
        snprintf(buf, buf_size,
                 "Audio: %s",
                 codec_name);
        if (profile)
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     " (%s)", profile);
        if (enc->codec_tag) {
            char tag_buf[32];
            av_get_codec_tag_string(tag_buf, sizeof(tag_buf), enc->codec_tag);
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     " [%s / 0x%04X]", tag_buf, enc->codec_tag);
        }

        av_strlcat(buf, "\n      ", buf_size);
        if (enc->sample_rate) {
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     "%d Hz, ", enc->sample_rate);
        }
        av_get_channel_layout_string(buf + strlen(buf), buf_size - strlen(buf), enc->channels, enc->channel_layout);
        if (enc->sample_fmt != AV_SAMPLE_FMT_NONE) {
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     ", %s", av_get_sample_fmt_name(enc->sample_fmt));
        }
        break;
    case AVMEDIA_TYPE_DATA:
        snprintf(buf, buf_size, "Data: %s", codec_name);
        break;
    case AVMEDIA_TYPE_SUBTITLE:
        snprintf(buf, buf_size, "Subtitle: %s", codec_name);
        break;
    case AVMEDIA_TYPE_ATTACHMENT:
        snprintf(buf, buf_size, "Attachment: %s", codec_name);
        break;
    default:
        snprintf(buf, buf_size, "Invalid Codec type %d", enc->codec_type);
        return;
    }
    if (encode) {
        if (enc->flags & AV_CODEC_FLAG_PASS1)
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     ", pass 1");
        if (enc->flags & AV_CODEC_FLAG_PASS2)
            snprintf(buf + strlen(buf), buf_size - strlen(buf),
                     ", pass 2");
    }
    bitrate = get_bit_rate(enc);
    if (bitrate != 0) {
        snprintf(buf + strlen(buf), buf_size - strlen(buf),
                 ", %d kb/s", bitrate / 1000);
    }
}

const char *av_get_profile_name(const AVCodec *codec, int profile)
{
    const AVProfile *p;
    if (profile == FF_PROFILE_UNKNOWN || !codec->profiles)
        return NULL;

    for (p = codec->profiles; p->profile != FF_PROFILE_UNKNOWN; p++)
        if (p->profile == profile)
            return p->name;

    return NULL;
}

unsigned avcodec_version(void)
{
    return LIBAVCODEC_VERSION_INT;
}

const char *avcodec_configuration(void)
{
    return LIBAV_CONFIGURATION;
}

const char *avcodec_license(void)
{
#define LICENSE_PREFIX "libavcodec license: "
    return LICENSE_PREFIX LIBAV_LICENSE + sizeof(LICENSE_PREFIX) - 1;
}

void avcodec_flush_buffers(AVCodecContext *avctx)
{
    if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME)
        ff_thread_flush(avctx);
    else if (avctx->codec->flush)
        avctx->codec->flush(avctx);

    if (!avctx->refcounted_frames)
        av_frame_unref(avctx->internal->to_free);
}

int av_get_exact_bits_per_sample(enum AVCodecID codec_id)
{
    switch (codec_id) {
    case AV_CODEC_ID_ADPCM_CT:
    case AV_CODEC_ID_ADPCM_IMA_APC:
    case AV_CODEC_ID_ADPCM_IMA_EA_SEAD:
    case AV_CODEC_ID_ADPCM_IMA_WS:
    case AV_CODEC_ID_ADPCM_G722:
    case AV_CODEC_ID_ADPCM_YAMAHA:
        return 4;
    case AV_CODEC_ID_PCM_ALAW:
    case AV_CODEC_ID_PCM_MULAW:
    case AV_CODEC_ID_PCM_S8:
    case AV_CODEC_ID_PCM_U8:
    case AV_CODEC_ID_PCM_ZORK:
        return 8;
    case AV_CODEC_ID_PCM_S16BE:
    case AV_CODEC_ID_PCM_S16BE_PLANAR:
    case AV_CODEC_ID_PCM_S16LE:
    case AV_CODEC_ID_PCM_S16LE_PLANAR:
    case AV_CODEC_ID_PCM_U16BE:
    case AV_CODEC_ID_PCM_U16LE:
        return 16;
    case AV_CODEC_ID_PCM_S24DAUD:
    case AV_CODEC_ID_PCM_S24BE:
    case AV_CODEC_ID_PCM_S24LE:
    case AV_CODEC_ID_PCM_S24LE_PLANAR:
    case AV_CODEC_ID_PCM_U24BE:
    case AV_CODEC_ID_PCM_U24LE:
        return 24;
    case AV_CODEC_ID_PCM_S32BE:
    case AV_CODEC_ID_PCM_S32LE:
    case AV_CODEC_ID_PCM_S32LE_PLANAR:
    case AV_CODEC_ID_PCM_U32BE:
    case AV_CODEC_ID_PCM_U32LE:
    case AV_CODEC_ID_PCM_F32BE:
    case AV_CODEC_ID_PCM_F32LE:
        return 32;
    case AV_CODEC_ID_PCM_F64BE:
    case AV_CODEC_ID_PCM_F64LE:
        return 64;
    default:
        return 0;
    }
}

int av_get_bits_per_sample(enum AVCodecID codec_id)
{
    switch (codec_id) {
    case AV_CODEC_ID_ADPCM_SBPRO_2:
        return 2;
    case AV_CODEC_ID_ADPCM_SBPRO_3:
        return 3;
    case AV_CODEC_ID_ADPCM_SBPRO_4:
    case AV_CODEC_ID_ADPCM_IMA_WAV:
    case AV_CODEC_ID_ADPCM_IMA_QT: