[FFmpeg-devel] [PATCH 3/7] api-band-test: use non-obsolete decoding API

[James Almer]

On 12/12/2020 12:45 PM, Anton Khirnov wrote:
> ---
>   tests/api/api-band-test.c | 90 +++++++++++++++++++++++----------------
>   1 file changed, 53 insertions(+), 37 deletions(-)
> 
> diff --git a/tests/api/api-band-test.c b/tests/api/api-band-test.c
> index 257e741694..34bed1d6be 100644
> --- a/tests/api/api-band-test.c
> +++ b/tests/api/api-band-test.c
> @@ -71,14 +71,12 @@ static int video_decode(const char *input_filename)
>       AVCodecParameters *origin_par = NULL;
>       uint8_t *byte_buffer = NULL;
>       AVFrame *fr = NULL;
> -    AVPacket pkt;
> +    AVPacket *pkt;
>       AVFormatContext *fmt_ctx = NULL;
>       int number_of_written_bytes;
>       int video_stream;
> -    int got_frame = 0;
>       int byte_buffer_size;
>       int result;
> -    int end_of_stream = 0;
>   
>       draw_horiz_band_called = 0;
>   
> @@ -135,6 +133,12 @@ static int video_decode(const char *input_filename)
>           return AVERROR(ENOMEM);
>       }
>   
> +    pkt = av_packet_alloc();
> +    if (!pkt) {
> +        av_log(NULL, AV_LOG_ERROR, "Cannot allocate packet\n");
> +        return AVERROR(ENOMEM);
> +    }
> +
>       if (strcmp(codec->name, "flv") && strcmp(codec->name, "mpeg4") && strcmp(codec->name, "huffyuv")) {
>           av_log(NULL, AV_LOG_ERROR, "Wrong codec\n");
>           return -1;
> @@ -155,48 +159,60 @@ static int video_decode(const char *input_filename)
>       memset(slice_byte_buffer, 0, byte_buffer_size);
>       slice_byte_buffer_size = byte_buffer_size;
>   
> -    av_init_packet(&pkt);
> -    do {
> -        if (!end_of_stream) {
> -            if (av_read_frame(fmt_ctx, &pkt) < 0) {
> -                end_of_stream = 1;
> -            }
> +    result = 0;
> +    while (result >= 0) {
> +        result = av_read_frame(fmt_ctx, pkt);
> +        if (result >= 0 && pkt->stream_index != video_stream) {
> +            av_packet_unref(pkt);
> +            continue;
>           }
> -        if (end_of_stream) {
> -            pkt.data = NULL;
> -            pkt.size = 0;
> +
> +        if (result < 0)
> +            result = avcodec_send_packet(ctx, NULL);
> +        else
> +            result = avcodec_send_packet(ctx, pkt);

avcodec_send_packet() accepts both NULL and a blank AVPacket to signal 
EOF, so no need for this check. av_read_frame() ensures pkt is blank on 
error, but it's not clear from the doxy if that also happens on EOF.

> +
> +        av_packet_unref(pkt);
> +
> +        if (result < 0) {
> +            av_log(NULL, AV_LOG_ERROR, "Error submitting a packet for decoding\n");
> +            return result;
>           }
> -        if (pkt.stream_index == video_stream || end_of_stream) {
> -            got_frame = 0;
> -            result = avcodec_decode_video2(ctx, fr, &got_frame, &pkt);
> -            if (result < 0) {
> +
> +        while (result >= 0) {
> +            result = avcodec_receive_frame(ctx, fr);
> +            if (result == AVERROR_EOF)
> +                goto finish;
> +            else if (result == AVERROR(EAGAIN)) {
> +                result = 0;
> +                break;
> +            } else 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 (draw_horiz_band_called == 0) {
> -                    av_log(NULL, AV_LOG_ERROR, "draw_horiz_band haven't been called!\n");
> -                    return -1;
> -                }
> -                if (av_adler32_update(0, (const uint8_t*)byte_buffer, number_of_written_bytes) !=
> -                    av_adler32_update(0, (const uint8_t*)slice_byte_buffer, number_of_written_bytes)) {
> -                    av_log(NULL, AV_LOG_ERROR, "Decoded frames with and without draw_horiz_band are not the same!\n");
> -                    return -1;
> -                }
> +
> +            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 (draw_horiz_band_called == 0) {
> +                av_log(NULL, AV_LOG_ERROR, "draw_horiz_band haven't been called!\n");
> +                return -1;
> +            }
> +            if (av_adler32_update(0, (const uint8_t*)byte_buffer, number_of_written_bytes) !=
> +                av_adler32_update(0, (const uint8_t*)slice_byte_buffer, number_of_written_bytes)) {
> +                av_log(NULL, AV_LOG_ERROR, "Decoded frames with and without draw_horiz_band are not the same!\n");
> +                return -1;
>               }
> -            av_packet_unref(&pkt);
> -            av_init_packet(&pkt);
> +            av_frame_unref(fr);
>           }
> -    } while (!end_of_stream || got_frame);
> +    }
>   
> -    av_packet_unref(&pkt);
> +finish:
> +    av_packet_free(&pkt);
>       av_frame_free(&fr);
>       avformat_close_input(&fmt_ctx);
>       avcodec_free_context(&ctx);
>