fix: VideoReader bugs — stride, memory, audio detection, UB

Pass MXL grain stride (from sliceSizes[0]) into get_next_frame so
YUV422P10toV210 writes with the correct line width instead of a
self-computed value that may not match the MXL buffer.

Fix audio stream detection: condition was inverted (!= -1 → == -1),
so the first audio stream was never picked up.

Add return false at end of get_next_frame to fix UB when g_running
goes false and the loop exits without returning.

Replace av_frame_unref/av_packet_unref with av_frame_free/av_packet_free
in destructor — unref only releases data, not the struct itself.

Add av_freep(&p10_data[0]) in destructor to free av_image_alloc memory.

Remove unused p10_buffer and v210_buffer allocations.

Read filename from config("file") instead of hardcoded path.
Add early return if mxlCreateFlowWriter fails.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
JohannesItten
2026-07-03 19:11:18 +03:00
parent 0b5b113d4e
commit bb7d1bb5a3
2 changed files with 15 additions and 33 deletions
+6 -6
View File
@@ -15,12 +15,10 @@ extern "C" {
#include "NodeBase.hpp"
#include "VideoReader.hpp"
#include <iostream>
class VideoInNode : public dmf::NodeBase {
void run() override {
std::string filename = "/home/itten/test-vid/0.ts";
const std::string filename = config().value("file", std::string{});
if (filename.empty()) { log("config missing 'file'"); return; }
log("VideoIn Node started with file: %s", filename.c_str());
dmf::VideoReader video_reader(filename);
@@ -51,8 +49,10 @@ class VideoInNode : public dmf::NodeBase {
&created
);
if (vst != MXL_STATUS_OK) {
log("MXL flow writer is not created. Reason: %s", dmf::mxl_status_str(vst));
log("mxlCreateFlowWriter failed (%s)", dmf::mxl_status_str(vst));
return;
}
const uint32_t video_stride = video_config.discrete.sliceSizes[0];
mxlRational video_rate = {fps_num, fps_den};
uint64_t video_index = mxlGetCurrentIndex(&video_rate);
@@ -62,7 +62,7 @@ class VideoInNode : public dmf::NodeBase {
mxlGrainInfo grain{};
vst = mxlFlowWriterOpenGrain(video_writer, video_index, &grain, &buf);
if (vst == MXL_STATUS_OK) {
if (!video_reader.get_next_frame(buf, nullptr)) continue;
if (!video_reader.get_next_frame(buf, video_stride, nullptr)) continue;
grain.flags = 0;
grain.validSlices = grain.totalSlices;
mxlFlowWriterCommitGrain(video_writer, &grain);
+8 -26
View File
@@ -49,11 +49,12 @@ class VideoReader {
avcodec_free_context(&codec_context);
avformat_close_input(&format_context);
sws_freeContext(sws_ctx);
av_frame_unref(frame);
av_packet_unref(packet);
av_freep(&p10_data[0]);
av_frame_free(&frame);
av_packet_free(&packet);
}
bool get_next_frame(uint8_t* video_buf, uint8_t* audiobuf) {
bool get_next_frame(uint8_t* video_buf, uint32_t mxl_stride, uint8_t* audiobuf) {
while (dmf::g_running.load(std::memory_order_relaxed)) {
// Try to get a buffered frame from previous packet first
if (avcodec_receive_frame(codec_context, frame) == 0) {
@@ -76,7 +77,7 @@ class VideoReader {
p10_linesizes[0],
p10_linesizes[1],
p10_linesizes[2],
v210_stride
mxl_stride
);
av_frame_unref(frame);
return true;
@@ -93,6 +94,7 @@ class VideoReader {
if (packet->stream_index != video_stream_index) continue;
avcodec_send_packet(codec_context, packet);
}
return false;
}
private:
@@ -105,11 +107,8 @@ class VideoReader {
// conversion data
struct SwsContext *sws_ctx{};
uint8_t* p10_buffer = nullptr;
int p10_linesizes[4] = {0, 0, 0, 0};
uint8_t* p10_data[4] = {nullptr, nullptr, nullptr, nullptr};
uint8_t* v210_buffer = nullptr;
int v210_stride = 0;
bool open_file(std::string filename) {
if (avformat_open_input(&format_context, filename.c_str(), nullptr, nullptr) != 0) {
@@ -130,7 +129,7 @@ class VideoReader {
if (data_type == AVMEDIA_TYPE_VIDEO) {
video_stream_index = i;
have_video = true;
} else if (data_type == AVMEDIA_TYPE_AUDIO && audio_stream_index != -1) {
} else if (data_type == AVMEDIA_TYPE_AUDIO && audio_stream_index == -1) {
// TODO: show list of available audio tracks and allow user to pick
// or handle multiple audio streams
audio_stream_index = i;
@@ -193,30 +192,13 @@ class VideoReader {
return;
}
// Allocate P10 image
int p10_buf_size = av_image_get_buffer_size(
AV_PIX_FMT_YUV422P10LE,
source_info.width, source_info.height,
64
);
p10_buffer = (uint8_t*)av_malloc(p10_buf_size);
// Allocate P10 image (freed in destructor via av_freep(&p10_data[0]))
av_image_alloc(
p10_data, p10_linesizes,
source_info.width, source_info.height,
AV_PIX_FMT_YUV422P10LE, 64
);
// Allocate v210 buffer
int blocks_per_row = (codec_context->width + 5) / 6;
int v210_bytes_per_row = blocks_per_row * 16;
v210_stride = ((v210_bytes_per_row + 63) / 64) * 64;
int v210_buffer_size = v210_stride * source_info.height;
v210_buffer = (uint8_t*)av_malloc(v210_buffer_size);
if (!v210_buffer) {
throw std::runtime_error("Failed to allocate V210 buffer");
return;
}
}
};