This example shows how to do HW-accelerated decoding with output frames from the HW video surfaces.
#include <stdio.h>
{
int err = 0;
fprintf(stderr, "Failed to create specified HW device.\n");
return err;
}
return err;
}
{
return *p;
}
fprintf(stderr, "Failed to get HW surface format.\n");
}
{
fprintf(stderr, "Error during decoding\n");
}
while (1) {
fprintf(stderr, "Can not alloc frame\n");
}
return 0;
fprintf(stderr, "Error while decoding\n");
}
fprintf(stderr, "Error transferring the data to system memory\n");
}
tmp_frame = sw_frame;
} else
fprintf(stderr, "Can not alloc buffer\n");
}
fprintf(stderr, "Can not copy image to buffer\n");
}
fprintf(stderr, "Failed to dump raw data.\n");
}
}
}
int main(
int argc,
char *argv[])
{
if (argc < 4) {
fprintf(stderr, "Usage: %s <device type> <input file> <output file>\n", argv[0]);
return -1;
}
fprintf(stderr, "Device type %s is not supported.\n", argv[1]);
fprintf(stderr, "Available device types:");
fprintf(stderr, "\n");
return -1;
}
fprintf(stderr, "Cannot open input file '%s'\n", argv[2]);
return -1;
}
fprintf(stderr, "Cannot find input stream information.\n");
return -1;
}
fprintf(stderr, "Cannot find a video stream in the input file\n");
return -1;
}
if (!config) {
fprintf(stderr, "Decoder %s does not support device type %s.\n",
return -1;
}
break;
}
}
return -1;
return -1;
fprintf(stderr,
"Failed to open codec for stream #%u\n",
video_stream);
return -1;
}
break;
}
return 0;
}
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
static enum AVPixelFormat hw_pix_fmt
AVPixelFormat
Pixel format.
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
int methods
Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible setup methods which can be used...
#define AVERROR_EOF
End of file.
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
This structure describes decoded (raw) audio or video data.
AVStream ** streams
A list of all streams in the file.
enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name)
Look up an AVHWDeviceType by name.
enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev)
Iterate over supported device types.
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
static const chunk_decoder decoder[8]
static enum AVPixelFormat get_hw_format(AVCodecContext *ctx, const enum AVPixelFormat *pix_fmts)
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
static enum AVPixelFormat pix_fmts[]
static AVCodecContext * decoder_ctx
enum AVPixelFormat pix_fmt
For decoders, a hardware pixel format which that decoder may be able to decode to if suitable hardwar...
const char * av_hwdevice_get_type_name(enum AVHWDeviceType type)
Get the string name of an AVHWDeviceType.
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it.
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
@ AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX
The codec supports this format via the hw_device_ctx interface.
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames,...
int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align)
Return the size in bytes of the amount of data required to store an image with the given parameters.
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
#define i(width, name, range_min, range_max)
int avformat_open_input(AVFormatContext **ps, const char *url, ff_const59 AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
static AVBufferRef * hw_device_ctx
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
int main(int argc, char *argv[])
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
static AVStream * video_stream
int av_hwdevice_ctx_create(AVBufferRef **pdevice_ref, enum AVHWDeviceType type, const char *device, AVDictionary *opts, int flags)
Open a device of the specified type and create an AVHWDeviceContext for it.
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags)
Copy data to or from a hw surface.
static FILE * output_file
main external API structure.
static int hw_decoder_init(AVCodecContext *ctx, const enum AVHWDeviceType type)
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
A Quick Description Of Rate Distortion Theory We want to encode a video
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
const AVCodecHWConfig * avcodec_get_hw_config(const AVCodec *codec, int index)
Retrieve supported hardware configurations for a codec.
A reference to a data buffer.
int av_image_copy_to_buffer(uint8_t *dst, int dst_size, const uint8_t *const src_data[4], const int src_linesize[4], enum AVPixelFormat pix_fmt, int width, int height, int align)
Copy image data from an image into a buffer.
This structure stores compressed data.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
enum AVHWDeviceType device_type
The device type associated with the configuration.
static int decode_write(AVCodecContext *avctx, AVPacket *packet)
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.